1) Remove all our PDU code and switch to the PDU code from the
klinker library
2) Switch to using the system Lollipop MMS library by default,
and falling back to our own custom library if that fails.
3) Format SMIL differently, using code from klinker instead of
what we've pieced together.
4) Pull per-carrier MMS media constraints from the XML config
files in the klinker library, instead of hardcoding it at 280kb.
Hopefully this is an improvement, but given that MMS is involved,
it will probably make things worse instead.
1) Display the individual sender name in a group conversation.
2) Add an "address" column to MmsDatabase and keep FROM there.
3) Remove all blocking operations from MmsDatabase.Reader path.
4) Strip SMIL and other undisplayable parts from part count.
5) Fix places where messages weren't being correctly decrypted.