librevenge: add recipe for version 0.0.0
nspr: add recipe and patchset for version 4.10.6 (still broken)

* I used Linux/Unix platform code with pthreads because BeOS one
  is very outdated.
* Some tests pass but there is a crash on exit.
Move catalog files for docbook to data/xml

These are not supposed to be configuration files.
gtk_doc: make the recipe work.
Pixman: update to latest version

* Cairo needs at least 0.22
* Also remove !x86_gcc2 restriction since it builds and passes all
tests.
Add itstool.
Add recipe for Harfbuzz.
Fix vigra_devel PROVIDES section
Style fixes for vigra recipe; bump revision
nss: add initial recipe based on Gentoo ebuild file

* Also mark nspr as broken