[Cin] Latex and Manual

[Andrea paz]

- Changed \geometry(right=3.0cm). Thanks, Andrey.
- I have inserted Igor's beautiful pdf in manual_latex. (Usual
address: https://www.dropbox.com/s/0js49r47s0qu621/CinelerraGG_Manual.pdf?dl=0)
- I had to force the pdf because they are present in ".gitignore". Did
I do wrong?

I take this opportunity to clarify how I insert the images: I use 144
Dpi PNG because, in my opinion, they are the minimum acceptable
quality. By minimum quality I mean: being able to easily read the
smallest text on the screen. If we make a version for printing we will
have to replace all the images. I propose to postpone this work until
after the completion of the manual.
What do you think? I'm fine with any solution. And, as always, the
last word is up to Phyllis.