Make grass.lib a package rather than a module

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@51229 15284696-431f-4ddb-bdfa-cd5b030d7da7

lib/python/ctypes/__init__.py

@@ -1,15 +1,16 @@
-import date
-import gis
-import raster
-import gmath
-import proj
-import imagery
-import vector
-import display
-import stats
-import dbmi
-import raster3d
-import arraystats
-import cluster
-import vedit
-
+__all__ = [
+    'date',
+    'gis',
+    'raster',
+    'gmath',
+    'proj',
+    'imagery',
+    'vector',
+    'display',
+    'stats',
+    'dbmi',
+    'raster3d',
+    'arraystats',
+    'cluster',
+    'vedit'
+    ]