SSP-518 Add cell phone field to external person model.

This is a cherry pick of c8263535e9d8fdfe174ad0a9f303bdb31e366809

Conflicts:
	src/main/resources/org/jasig/ssp/database/masterChangeLog.xml
	src/main/webapp/app-all.js
	src/test/resources/org/jasig/ssp/database/masterChangeLog-test.xml