Bug: Invalid IDs resulted in 500.

VideoInfo now always returns an obj, so reverting
to checking if the video-info has a title.
It has no title if no video was found.
Need to make overlay easier.

Add_overlay is now responsible for finding the overlay-file.
Add option to override overlay-image in local environment.
Merge branch 'feature/site' into develop

* feature/site:
  Add option to override overlay-image in local environment.
  Need to make overlay easier.
Bump filename
Merge branch 'release/0.6.0' into develop

* release/0.6.0:
  Bump filename