Update version.rb

bump version to get latest changes
Merge pull request #1 from outright/bump-version-0-3-1

Update version.rb
Handle cases where model.get(relation.key) is undefined

There are cases where a relation is not set. Don't clearDeletedModelsFor undefined collection or model.
Update version.rb
Merge pull request #3 from outright/handle-nil-associations

Handle nil associations