-BlockAllocator is no longer template

-Multithreaded IDManager.getNewID()
 *use implementation with free IDs stack (instead of classic pool)
-support for multiple UpdatePasses. Passes are added by name, and must be called between begin() end() functions.
-removed mutex from addEntity()
-commit() function added. Used to commit all changes made while update() call. Called automatically by begin() end() functions.

source/ecs/block_allocator.d

@@ -5,8 +5,11 @@ import ecs.manager;
 import std.experimental.allocator;
 import std.experimental.allocator.mallocator : AlignedMallocator, Mallocator;
 
-struct BlockAllocator(uint block_size, uint blocks_in_allocation)
+struct BlockAllocator//(uint block_size, uint blocks_in_allocation)
 {
+    private uint block_size;
+    private uint blocks_in_allocation;
+
     void* next_block = null;
 
     void* getBlock()