Mostly, the inheritance graph for MessageRecord/MmsMessageRecord was
all messed up, and each class was overloaded for things it shouldn't
have been.
1) Broke MessageRecord/MmsMessageRecord up into: DisplayRecord, ThreadRecord,
MessageRecord, SmsMessageRecord, NotificationMmsMessageRecord, and
MediaMmsMessageRecord.
2) Updated all the adapters/views to keep pace with that change.
1) Change all instances which use concatenation to build strings
with variables in them to use string formatting instead.
2) Extract all string literals from layouts and menus into strings.xml
3) Extract all string literals from code into strings.xml
