Merge pull request #4 from abiligiri/master

Get the group list to show some sample data from firebase
Add TokenAutoComplete to libs
This helps in displaying spannable labels in the field used
to add participants to a group
Update security.rules to user string ids for user
Using numbers as user ids causing problems with reading. Free standing
numbers at any level is json are treated as array indices and null is present
in indices that are missing
Get create group to work
Integrated the TokenAutoCompleteView
Change code to create records using the user's unique id which is a combination of
login type and the numeric id
Rename AccountRegister to SignIn
Rename ConversationCompose to CreateGroup
Rename activity layout xmls
Added Messages Activity
This shows the messages in a group. Updates as new messages sent/received
Make the list always scroll to bottom on updates