Renamed XImpl to AbstractX (More consistent)

Where * is Buffer, Hash and Shader


Former-commit-id: a99681ab1d515c9b39e6ba5f447c9000ef1092b8

include/Nazara/Core/String.hpp

@@ -302,7 +302,7 @@ class NAZARA_API NzString : public NzHashable
 
 	private:
 		void EnsureOwnership();
-		bool FillHash(NzHashImpl* hash) const;
+		bool FillHash(NzAbstractHash* hash) const;
 		void ReleaseString();
 
 		SharedString* m_sharedString;