Addition of app lock for each app

[SUBBU15520]

Let's be honest secure folder is a unique way of implementing app lock but far from user friendly n has many flaws like

1. Doesn't lock app separately

2. Duplication of app

3. Imagine if your device gets snatched when you have unlocked secure folder.

All of the following cons can be avoided by individually locking each app and for 3. Only the app unlocked will be at risk rather than all