Doc & code improvements.

Better encapsulation.
Removed ivars in favor of properties.
Added kCoverViewTag constant to replace the hard coded 99.

Readme update.

Fixed the passcode not locking

if the change/remove passcode view was on screen when going to
background.

Merge pull request rolandleth#36 from kaneshin/localization_japanese

Add localized string for Japanese

Changed timers to NSTimeInterval.

Changed timerDuration to be saved to the keychain.
Nothing is saved to userDefaults anymore, to increase security.

Revert "Added a setter for max number of allowed failed attempts"

This reverts commit 98dd3c9.

Merge branch 'pr/29'

Merge pull request rolandleth#28 from anasb/master

Added option to display a logout button on a navigation bar during the...

Merge pull request rolandleth#27 from anasb/master

Possibility to use custom username & service name

Merge pull request rolandleth#23 from anasb/master

Adding possibility to customize the navigation bar's tintColor, barTintColor and titleColor.