Common update:

-added multiple new function to allocate template and add entity
-updated README.md (complete initial version)
-empty components now don't take memory
-fixedd small bug with TestRunner
-added many new tests (HashMap, Vector, EntityMeta, ...)
-added default hashing function to HashMap
-fixed critical bug with adding entities
-fixed small bug with adding entity with remplacement components
-added asserts into code to better bug detection
-small performance improvement for events
-added ComponentRef structure which contain data pointer and componentID
-remove EntityID from Event structure
-now events are handled before removing entiteis
-fixed GDC compilation
-fixed rendering of rotated sprites
-added weapons as separate entities to space ship and others
-added Tower enemy to SpaceInvaders demo
-added Boss to SpaceInvaders demo (boss has four tower attached to it)
-Boss towers shoot multiple bullets upon death
-fixed critical bug with demos switching
-fixed critical bug related to adding/removing entities form inside onAdd/onRemove entity callback
-added animation support
-added particles sypport and particles for firing and explostions, and more
-multithreaded rendering now has same rendering order as singlethreaded
-application automaticallu detect host CPU threads count
-added upgrades to SPaceInvaders demo
-fixed texture memory freeing
-improved documentation
-improved multithreaded performance
-improve shader code
-fixed registration issue
-some additional performance improvements
-added depth and colors to rendering parameters
-jobs now has names corresponding to their systems
-change execute() -> willExecute()
-added EntityMeta structure to speedup getting fetching components form entity
-improved multithreading rendering
-added possibility tio change number of threads runtime
-added bullets collision detection in SpaceInvaders demo
-some CI changes
-added VBO batch rendering (current default, no render mode switch yet)
-fixed camera positioning calculation
-fixed buffer issue with WebGL
-added viewport scalling (at least 300 pixels height). Pixels are scalled if screen is bigger.
-center demos gameplay area
-added fullpage html template for Emscripten build
-added many new sprites to atlas
-fixed critical bug with CPU usage in multithreaded mode
-snake render tile coresponding to body part
-snake is destroyed after collision and emit some particles
-added some functionality to vectors
-fixed documentation issue in Manager.d
-more minor code changes and cleanup

source/ecs/block_allocator.d

@@ -1,97 +0,0 @@
-/************************************************************************************************************************
-It's internal code.
-
-Module contain memory allocator.
-
-Copyright: Copyright © 2018-2019, Dawid Masiukiewicz, Michał Masiukiewicz
-License: BSD 3-clause, see LICENSE file in project root folder.
-*/
-module ecs.block_allocator;
-
-import ecs.manager;
-import ecs.std;
-
-/************************************************************************************************************************
-Allocator allocate large blocks and return smaller blocks. When there is no more blocks then next large block is allocated.
-By default freeing memory only returns it to allocator. To free large memory chunks freeMemory function is used.
-freeMemory function return to system memory even if chunk blocks wasn't freed.
-*/
-struct BlockAllocator
-{
-    /************************************************************************************************************************
-    Get new block. Allocator automatically allocate next memory chunk if needed.
-    */
-    void* getBlock() nothrow @nogc
-    {
-        if (next_block is null)
-            allocBlock();
-        void* ret = next_block;
-        next_block = *cast(void**) next_block;
-        return ret;
-    }
-
-    /************************************************************************************************************************
-    Return block to allocator for further use.
-    */
-    void freeBlock(void* block) nothrow @nogc
-    {
-        *cast(void**)block = next_block;
-        next_block = block;
-    }
-
-    /************************************************************************************************************************
-    Free whole used memory. This function return to system all memory chunks even if not every black was freed.
-    */
-    void freeMemory() nothrow @nogc
-    {
-        while(pointers)
-        {
-            foreach(i;0..pointers.numberof)
-            {
-                Mallocator.alignDispose(pointers.blocks[i]);
-            }
-            BlockPointers* next_pointers = pointers.next_pointers;
-            Mallocator.dispose(pointers);
-            pointers = next_pointers;
-        }
-    }
-
-private:
-
-    void allocBlock() nothrow @nogc
-    {
-        next_block = cast(void*) Mallocator.alignAlloc(
-                block_size * blocks_in_allocation, block_size);
-
-        if(pointers is null)pointers = Mallocator.make!BlockPointers;
-        if(pointers.numberof >= 32)
-        {
-            BlockPointers* new_pointers = Mallocator.make!BlockPointers;
-            new_pointers.next_pointers = pointers;
-            pointers = new_pointers;
-        }
-        pointers.blocks[pointers.numberof++] = next_block;
-
-        foreach (i; 0 .. blocks_in_allocation - 1)
-        {
-            void** pointer = cast(void**)(next_block + i * block_size);
-            *pointer = next_block + (i + 1) * block_size;
-        }
-        void** pointer = cast(void**)(
-                next_block + (blocks_in_allocation - 1) * block_size);
-        *pointer = null;
-    }
-
-    struct BlockPointers
-    {
-        void*[32] blocks;
-        uint numberof = 0;
-        BlockPointers* next_pointers = null;
-    }
-
-    uint block_size;
-    uint blocks_in_allocation;
-
-    void* next_block = null;
-    BlockPointers* pointers = null;
-}