Signup: remove unused segue
Settings: Let user pick notification style

Also lets user search for contacts by phone number.
Fingerprint verification instructions
Receiving and displaying attachements
Adding Clang Format file
Fixing crash on notification style setting
Attachements: Fixing UI issues
Rename to 'attachment'
Attachments: Sending and receiving
Merge remote-tracking branch 'upstream/textSecure' into textSecure