gitclone: don't raise when uninstall if location does not exist.

slapos/recipe/gitclone.py

@@ -259,6 +259,8 @@ class Recipe(object):
 def uninstall(name, options):
   """Keep the working copy, unless develop is set to false.
   """
+  if not os.path.exists(options['location']):
+    return
   force_keep = False
   if options.get('develop', 'yes').lower() in TRUE_VALUES:
     p = subprocess.Popen([options.get('git-executable', 'git'), 'status', '--short'],