Merge pull request #19 from asobolev/master

Serializer implementation with play Format, Reads, Writes

Looks fine for me
ConferenceService: all implementations complete and tested
Merge pull request #21 from stoewer/master

ConferenceService: all methods implemented and tested

LGTM
Merge pull request #25 from asobolev/master

Tests prototype for the Serializer

Is OK
updated routes in line with the model changes. updated Controllers accordingly
Merge branch 'andrey'