[Gzz] xupdf

[Tuomas Lukka]

Hi, now it seems that the texture lazy loading and caching is working - please 
test.
You can either run your own mstmpimg through gfx/util/texpacker.py or use the 
one
from io, provided that you have S3TC in your card  - if not, please contact me,
as texpacker needs to be fixed to understand that.

Next, the user interface adjustments. Benja: what parts of text notes, cells &c 
did
you already implement? 

What should we aim for: should we try to incorporate spatial (pp) features into 
this?

        Tuomas