Bug 833229 - 3.d/4: DOM implementation
Bug 833229 - 3.e/4: implement GonkVoicemailService
Bug 833229 - 3.f/N: voicemail service factory
Bug 833229 - 3.g/4: shutdown voicemail service
rename pdu_builder.js
Bug 833229 - 4/4: test cases.