Don't display sender in outgoing message details

Because we don't know it. Fixes WhisperSystems#711.
Don't show letter count inside a push group or when SMS mode is disabled
Merge pull request #805 from wickedshimmy/fix-sender-details

Don't display sender in outgoing message details
Merge pull request #795 from benalbrecht/nocount

Don't show letter count when SMS mode is disabled
Add option to disable screen security

See WhisperSystems/TextSecure#788
Merge pull request #794 from SamWhited/issue788

Add option to disable screen security
Update behavior for incoming SMS path.

1) On KitKat, unencrypted SMS messages are never stored in
   TextSecure unless it is set as the system-wide default.

2) On KitKat, if TextSecure is set as the system-wide default,
   provide an option to change the default to a different app.

3) Don't store the TextSecure challenge on KitKat+ devices.
Better support for local storage with passphrase disabled.

1) Never get into a state where messages aren't displayed
   unencrypted.

2) Fix bug where locked DB required launching twice.
Use modern icons in info and alert dialogs for ICS+
make bithub price update // FREEBIE

thanks lilia
Add contributing.md // FREEBIE

This file is recognized by github and presented to users who are trying
to open issues and submit pull requests.

Hopefully this more prominent placement will help deter people from
opening issues/prs for translation fixes.
Merge pull request #921 from liliakai/master

Add contributing.md // FREEBIE
Fix the send button's touch highlight color

Introduce a generic touch highlight background drawable, and use the
proper shades of blue (and gray on v19+).
Use the touch highlight background for the emoji toggle
Add touch highlight to contact photos
Use unified touch highlight in import & export
Replace the attachment dialog header icon with something modern
End conversation selection action mode if all deselected

This seems to be common convention in most apps.
Add missing spaces
a little typo mistake