Allow compiling with png support in codeblocks

projectfiles/CodeBlocks/wesnoth.cbp

@@ -37,6 +37,7 @@
 			<Add option="-Wno-strict-aliasing" />
 			<Add option="-Wno-missing-braces" />
 			<Add option="-DHAVE_PYTHON" />
+			<Add option="-DHAVE_LIBPNG" />
 			<Add option="-DUSE_GZIP" />
 			<Add option="-D_WIN32_WINDOWS" />
 			<Add option="-D_WIN32_WINNT=0x0501" />
@@ -76,11 +77,14 @@
 			<Add library="libboost_bzip2-mgw45-mt-1_57.a" />
 			<Add library="libboost_filesystem-mgw45-mt-1_57.a" />
 			<Add library="libboost_locale-mgw45-mt-1_57.a" />
+			<Add library="libpng" />
 			<Add directory="./" />
 		</Linker>
 		<Unit filename="../../packaging/windows/wesnoth.rc">
 			<Option compilerVar="WINDRES" />
 		</Unit>
+		<Unit filename="../../src/SDL_SavePNG/savepng.cpp" />
+		<Unit filename="../../src/SDL_SavePNG/savepng.h" />
 		<Unit filename="../../src/about.cpp" />
 		<Unit filename="../../src/about.hpp" />
 		<Unit filename="../../src/actions/attack.cpp" />