added isis support to quagga, fixed a bug in the renderer
cleaned comments
fixe cache issue.

Won't render otherwise

the two path joined were both absolute. Now, use relative "base" isntead of full_base to build the base_cache_dir
Merge pull request #89 from bhesmans/fixCache

fixe cache issue.
Merge pull request #88 from metaswirl/master

First pull request :)