huge cleanup and conversion of most string handling (especially paths) to unicode

please note: format strings must be %hs for char* arguments and %ls for
wchar_t*

This was SVN commit r7161.

source/simulation/EntityManager.cpp

@@ -224,7 +224,7 @@ HEntity CEntityManager::Create(CEntityTemplate* base, CVector3D position, float
 		m_nextalloc++;
 		if(m_nextalloc >= MAX_HANDLES)
 		{
-			debug_warn("Ran out of entity handles!");
+			debug_warn(L"Ran out of entity handles!");
 			return HEntity();
 		}
 	}