Added possibility to customize the Separator line below the Navigation Title Bar so you can change it's height, color or even totally disable/remove it.

Hi Manzel,

First of all thanks for your great work on this project and especially to open source it, I have made a few changes and would like to request a pull for them if you accept it, also have some few other ideas that I will try to implement in the future and let you know but as I'm sure you know one step at a time :)

FYI: I'm using KitKat so I can test for you if you wish, you can contact me or on email or on im, all the contact details are at pijulius.com and gtalk user is pijulius, and also will try to help you with whatever I can, so if you have any todo list that you would need help with you are welcome to forward it to me and will try to see if I can overcome them with my current knowledge :)

Thanks again!
Julius