Update Readme in GridLayout support lib.

This explains better how to deal with custom attributes when using
this version of GL instead of the frameworks one.

Change-Id: I1bcf7fad95d7c0c6884232833a0a75799857dadb
1 file changed
tree: b5e012f76058021a4aff0c5ecf6ee0c96d43c027
  1. v13/
  2. v4/
  3. v7/
  4. volley/