Patch [#22339] File/installation paths changes

Patch Tracker: http://projects.blender.org/tracker/?func=detail&aid=22339&group_id=9&atid=127

This patch implements the proposal outlined here:
http://wiki.blender.org/index.php/Dev:2.5/Source/Installation/Proposal

Original patch by Matt Ebb.
Contributions by Nathan Letwory, Damien Plisson and Andrea Weikert

NOTE:
This is a work in progress commit, some work still needs to be done on the SCons and CMake files for this to work properly, but at least should compile and the files should be created in the right directory.

Commit discussed on IRC with Ton and Campbell.

source/blender/python/intern/bpy.c

@@ -145,7 +145,7 @@ void BPy_init_modules( void )
 	PyObject *mod;
 
 	/* Needs to be first since this dir is needed for future modules */
-	char *modpath= BLI_gethome_folder("scripts/modules", BLI_GETHOME_ALL);
+	char *modpath= BLI_get_folder(BLENDER_SCRIPTS, "modules");
 	if(modpath) {
 		// printf("bpy: found module path '%s'.\n", modpath);
 		PyObject *sys_path= PySys_GetObject("path"); /* borrow */