Add model for trip
Add view and validation for create trip

Add stubs for trip view, edit and delete
Merge branch 'develop' into trip_management
Add edit trip

Change unique trip title per user validation
Add delete trip

Reload trip in edit when trip title is not unique
Add view trip feature with mapbox map
Add forgotten stylesheet
Change map to leaflet, add alternative basemap layers
Add created and modified fields to trip model
Add public checkbox to edit form and change trip view and edit behavior due to public value
Change order of trips in trips index, add slice from description to trips index
Add share trip

Adding users and groups, removing users and groups
Change check for view shared trips
Add trip stats
Merge branch 'trip_management' into develop

Issue #3
Merge branch 'develop'