Fixed #438. Fixed #504. Add a "Not After" date so that scheduled calls are not made after that time. Expose 'Not After' date through API.
Merge branch 'stable' into release-2.4

Conflicts:
	app/controllers/call_flows_controller.rb
	app/controllers/call_logs_controller.rb
	app/models/call_log.rb
	broker/src/util.erl
	config/deploy.rb
Fix test
Fetch alto_guisso from GitHub
Added status column (active, completed, failed) to call log CSV. Fixes #532
Download project phone book as CSV, including some usage stats per contact.
Fixes #516: User with shared project gets access denied through Phone Book API
Fixed alto_guisso repository location
Fixed #520: Allow user to specify SMS channel in Send SMS step
Add call duration to the status callback
Fixes #612: Added phone_number as an implicit (readonly) variable
Merge from release-2.4 branch
Merge branch 'hotfix-2.3.10'
Merge branch 'not_after'
Merge branch 'master' into scheduled-calls