Tidy up grunt configuration
Use GIF images if available

Closes #180
Handle events with no courses defined

Temporary fix to avoid problem. Would need a lot more work to implement
fully, although it might be useful in future. Partial solution for #179
Improved georeferencing

Original world file now saved so it can be used if the map is re-used.
Closes #181.
Improved error handling for new installation

Nothing clever but better than it was. Closes #182
Version 0.9.1

Formal release
Merge pull request #183 from Maprunner/dev

Version 0.9.1