* Ensure all controls visible at all times, on all form factors, even with keyboard active.
* Improve focus (i.e. auto-focus textfield on arrival and after errors).
* Move to programmatic view creation and layout.
* Improve spacing and sizing.
* Replace “change number” button with “back” button.
* Submit code with return key.
* Improve copy for clarity.
// FREEBIE
- Using same clang format file for old and new files.
- Moving out all TextSecure code to allow other clients (OS X, iOS) to
integrate easily TextSecure functionality.
- Use TextSecure API to signup.
• enables the "Send Again button"
• enables the display of the number the user entered in the Registration View in this subsequent scene (so they can see whether they should go back or not)
• enables the "call me instead button"
Reviewed-by: @FredericJacobs
