Filesystem handling is now more flexible

- removed CResourceLoader class in favor of one that implements resource loader interface
- removed global pool of files, in favour of more dynamic approach
- renamed some files to match current situation
All these changes are needed mostly for future mod manager + .zip support

lib/filesystem/CBinaryReader.h

@@ -1,3 +1,4 @@
+#pragma once
 
 /*
  * CBinaryReader.h, part of VCMI engine
@@ -9,8 +10,6 @@
  *
  */
 
-#pragma once
-
 class CInputStream;
 
 /**