Added Password Protection (whole app and note deletion)

[WillBBHM]

I have made the modifications for this second pull request as requested.

What is it?

• Bugfix
• Feature
• Codebase improvement

This is the link of the feature request :
#17

Description of the changes and new features

• Added Password protect the whole aplication
• Added Password of the app protect notes deletion
• Added a new settings section to the settings menu, with a checkbox to enable or disable application password protection.
  (Request user to create a password)

Screenshots

• New Settings "password" added in settings menu:
  
• App protection at start:
  
• Notes deletion protection (after confirmation delete):
  

Acknowledgement

• I read the contribution guidelines.

[Aga-C]

Now app blocking works like in other apps, thanks!

There are few more things to do:

1. Deletion protection should be a separate option. Check other apps how it works there (Gallery or File Manager). When you'll add this option, please add a new string for it: Password protect note deletion, don't reuse the existing one.
2. Please move Security section in Settings to be between Saving and Migration.

[WillBBHM]

I've just finished making the small changes requested.

[Aga-C]

I've tested and it works fine. Please now wait for final review from Naveen.

[WillBBHM]

Okay, that's great! I hope for a positive response!!

[onegladius]

Thank you for your work!

[WillBBHM]

Thank you very much, now all that’s left is to wait for Naveen to merge my contribution into the main project!!

[theKaido]

Hello, @naveensingh can we get an estimate of when this pull request will be validated? We need the validation to receive a rating. Thanks you

[naveensingh]

Sorry I can't provide an ETA, it'll reviewed after I'm done updating some other apps and after the Clock app is released. I'll try to get here by the weekend.

[theKaido]

thank you for your answer

[naveensingh]

Looks good to me! Sorry, it took me this long to get here.

[theKaido]

Thank you , Don't Worry about that ;)