samir,akula| #849| Moved campaign modules to github

Disabled pillreminder, message-campaign and scheduletracking modules
from main pom.xml as they've moved to a new repo on github -
https://github.com/motech/platform-campaigns

Change-Id: I5964249887160c868fa9598c413aebb93a49fa32
Merge "samir,akula| #849| Moved campaign modules to github"