Add TAILS cli install documentation
This adds two new commands to the CLI interface

We add two new commands with this commit:
status <-- Prints the current status to the terminal.
quit <-- A simple command to exit the program.
Fix compile and 'quit' by returning from mainUI.
Tweak TAILS instructions.
Merge branch 'ioerror-doc'
Add 'Delete' button for outbox messages.
go fmt run and call Sync() when writing statefile.
Merge branch 'coruus-master'