Created AbstractCalendarEntityManager and AbstractCalendarModule
This reduces duplicate code between Event and Commitment
Also separates databasey stuff from functionality stuff
Merge branch 'dev' of local repository into wip/model-and-manager-abstraction
Fixed a few calls to fromJSON*
Merge pull request #8 from bigamckay/wip/model-and-manager-abstraction

Merge wip/model and manager abstraction into dev