* src/preferences.h,
	  src/preferences.c,
	  src/preferences_gui.c:

	  Adds the functionality to Anjuta to auto save your unsaved
	  files before you build a project.

	  Patch submitted by:
	  jason <jason_williams@suth.com>

	* src/anjuta.[h,c]:
	  Added function for save all files.

	* src/mainmenu_callbacks.c:
	  Modified to use the above function.

	* src/build_project.c:
	  Save all files before build if it is set in the
	  preferences.