add paper_trail
refactor mappable + add paper_trail to geo_data and maps
versions_controller + versionable route concern
starting version list
track changes made
add version_presenter + version headline
diffs
diffs for contacts and jsontables
small refactor for values names
diff for changed location
object reversion working
login required for staring
fix reversion for location
show version preview
add spinners
specs for history and revert on versions_controller
more specs to versions_controller
version_presenter specs
diff presenter specs
Merge pull request #58 from it3s/versioning

Versioning