#138 Update the Occurrence

1. Updating the occurrence
2. Record update notes
3. Record fields changed on the occurrence update
4. Views to update occurrence
Merge remote-tracking branch 'upstream/master'
This closes #138

1. UpdateOccurrenceController small refactor in the paths
2. Add list of OccurrenceUpdate in the Occurrence model
3. Added labels in the properties
4. Added the list of updates in the occurrence detail view
5. Added button to edit the occurrence in the list of occurrences
Merge pull request #162 from efraimgentil/master

Update a Occurrence