[evince] Added New Functionalities + Some TODOs

[Arshad Husain <arshad husain1 gmail com>]

Hello,

I've added the ability for Evince to: 

- underline 

- strike-through

- choose between different annotation colors.

- designed and implemented new and more relevant icons (based off of gnome scalable icons) for annotations toolbar

I've also made a few refinements to annotation features:

- Not showing annotation tooltips on all types of annotations if comment is either empty or all whitespace. 

My immediate TODOs:

- Create undo function (if not already implemented) or improve undo function.

- Convert PS files to PDF format for viewing/annotating (PS reader problematic; let's discuss). Apple's Preview converts PS to PDF for viewing/annotating. 

- General bug fixing of my additions.

I still have to make sure that my fork of evince will run on another computer. I'm looking forward to working with all of you.

Thanks,

Arshad Husain