LibCore: Add a CConfigFile class, a simple INI file parser.

You open the configuration for an app like so:

    auto config = CConfigFile::get_for_app("MyApp");

This will then open ~/MyApp.ini and parse it for you.
Immediately start using it in Minesweeper to load the field size and mine
count from a config file.

LibCore/Makefile

@@ -13,6 +13,7 @@ OBJS = \
     CObject.o \
     CTimer.o \
     CEventLoop.o \
+    CConfigFile.o \
     CEvent.o
 
 LIBRARY = libcore.a