Use fontconfig for linux/mac

This uses fontconfig for looking up font files for freetype to use on
both linux and mac.  It's apparently a bit more optimal and prevents us
from having to worry about the load time on the mac version as well.

Refactored and moved all the old code to the find-font-windows.c file,
as it's no longer used on anything but windows.

cmake/Modules/FindFontconfig.cmake

@@ -0,0 +1,39 @@
+# Once done these will be defined:
+#
+#  FONTCONFIG_FOUND
+#  FONTCONFIG_INCLUDE_DIRS
+#  FONTCONFIG_LIBRARIES
+#
+
+if(FONTCONFIG_INCLUDE_DIRS AND FONTCONFIG_LIBRARIES)
+	set(FONTCONFIG_FOUND TRUE)
+else()
+	find_package(PkgConfig QUIET)
+	if (PKG_CONFIG_FOUND)
+		pkg_check_modules(_FONTCONFIG QUIET fontconfig)
+	endif()
+
+	find_path(FONTCONFIG_INCLUDE_DIR
+		NAMES fontconfig/fontconfig.h
+		HINTS
+			${_FONTCONFIG_INCLUDE_DIRS}
+		PATHS
+			/usr/include /usr/local/include /opt/local/include)
+
+	find_library(FONTCONFIG_LIB
+		NAMES fontconfig
+		HINTS
+			${_FONTCONFIG_LIBRARY_DIRS}
+		PATHS
+			/usr/lib /usr/local/lib /opt/local/lib)
+
+	set(FONTCONFIG_INCLUDE_DIRS ${FONTCONFIG_INCLUDE_DIR}
+		CACHE PATH "fontconfig include dir")
+	set(FONTCONFIG_LIBRARIES "${FONTCONFIG_LIB}"
+		CACHE STRING "fontconfig libraries")
+
+	include(FindPackageHandleStandardArgs)
+	find_package_handle_standard_args(Fontconfig DEFAULT_MSG FONTCONFIG_LIB
+		FONTCONFIG_INCLUDE_DIR)
+	mark_as_advanced(FONTCONFIG_INCLUDE_DIR FONTCONFIG_LIB)
+endif()