Create Settings.bundle

For several settings and acknowledgements in Settings.app.
Create .gitignore

I configured .gitignore for Cocoapods.
Untrack unneeded Xcode auto-generated files

Unneeded Xcode created files, such as *.xcuserstate, should not be
tracked.
Add new library named CRGradientNavigationBar

Added gradient coloured navigation bar library.
More details: https://github.com/chroman/CRGradientNavigationBar