Mms: Remove text/plain for ACTION_SEND

Always display registered apps for android.intent.action.SEND action, but this is not true.
Actually, it doesn't support that mime/type. Just remove it to avoid unexpected behaviour for
external apps.

See ComposeMessageActivity#addAttachment

Change-Id: I4815a59533dbfc3decfbdbc57bf456ebda3cab7a
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
Templates: back button goes to preferences not conversation list

Change-Id: Ib12e521b5049b0139ad638edb3a1583c3410cac5
Change default value of group message as mms to false.
Mms: add blacklist functionality

Taken from the patch for the Phone app.

Original code written for CM7 by Cytown, Cyanogen and nhnt11.

Modified for CM10.1 by Danny Baumann and dvtonder.

Adapted for the MMS app by jt1134.

Change-Id: Ie229c31fbac3f6b9cb311664c446228e0aaae588

Conflicts:
	AndroidManifest.xml
	res/values/strings.xml
	res/xml/preferences.xml
	src/com/android/mms/transaction/SmsReceiverService.java
	src/com/android/mms/ui/MessagingPreferenceActivity.java