Add password strength validation
At the moment there's no real password strength validation. It would be nice if Bitmask Android would have a similar ui element (enhanced text field) that shows the strength of the current password the user has typed in. A nice example can be found here: https://github.com/vishesh/sealnote/blob/master/Sealnote/src/main/java/com/twistedplane/sealnote/crypto/PasswordQuality.java and here: https://github.com/vishesh/sealnote/blob/master/Sealnote/src/main/java/com/twistedplane/sealnote/view/PasswordInput.java