Move GRAMPS_RESOURCE default into grampsapp.main()

Gramps.py

@@ -25,7 +25,5 @@ able to run gramps from the source directory without setting PYTHONPATH
 
 From this position, import gramps works great
 """
-import os
-os.environ['GRAMPS_RESOURCES'] = os.path.dirname(os.path.abspath(__file__))
 import gramps.grampsapp as app
 app.main()

gramps/grampsapp.py

@@ -442,6 +442,10 @@ def run():
         startcli(error, argpars)
 
 def main():
+    if 'GRAMPS_RESOURCES' not in os.environ:
+        resource_path, filename = os.path.split(os.path.abspath(__file__))
+        resource_path, dirname = os.path.split(resource_path)
+        os.environ['GRAMPS_RESOURCES'] = resource_path
     errors = run()
     if errors and isinstance(errors, list):
         for error in errors: