-fixed some meson issues on windows (becs and tests compilation works. Demos not yet)

-now tests compile proper files
-added setjmp bindings for Windows. It doesn't work on LDC build (singal API could works)

tests/meson.build

@@ -1,10 +1,18 @@
 tests_src = files(
-	'tests.d',
+	'access_perf.d',
+	'basic.d',
+	'bugs.d',
+	'id_manager.d',
+	'map.d',
+	'perf.d',
+	'runner.d',
+	'time.d',
+	'vector.d'
 )
 
 exe = executable('decs-tests',
 	tests_src,
-	include_directories : [inc],
+	include_directories : [inc, include_directories('..')],
 	d_args : args,
 	link_args : link_args,
 	dependencies : decs_dep,