Implemented test to demonstrate the issue

Issue is: When field photo is not set there will be an issue on the
save() call from CakePHP. Though saving should be possible without any
issues. The behaviour should ignore the save.
Fixed the issue

Added a check to see if the field is available at all before checking
for a uri.
Merge pull request #141 from lucfranken/FixForNoticeWhenFieldNotSet

Fix for notice when field not set