Merge pull request #7 from est77/master

Added gitignore. Ignore python compiled files.
Set default value for rendering passes to 1.
Merge pull request #8 from est77/est

Set default value for rendering passes to 1.
tweaked license.
Update README.md
Update README.md
-Added Linux support (OSX support as well? More testing needed)
-Added material nodes. They are written to the .appleseed file as well.  A small bug: if two materials share a node tree, it will write duplicate nodes, causing errors when loading file.
-project_file_writer.pyx can be compiled for faster .appleseed file generation
Merge branch 'master' of https://github.com/appleseedhq/blenderseed
-Added new light emission properties to UI: cast indirect, importance multiplier, light near start
-Forgot to update util.py
-Fixed bug with duplicate nodes being written to .appleseed file by prepending material name to the node name.  -May be more efficient to collect nodes in a set and check the set before emitting.
project_file_writer.py wasn't updated with new changes to project_file_writer.pyx
fixed bug in project_file_writer that didn't write BSDF names correctly in BSDF Blend.
Fix for addon_dir if more then 2 addon script paths
Fixed typo for unregistering class AppleseedSpecBRDFNode
Merge pull request #9 from jasperges/master

Small fixes based on my tests on OSX
Updated util.pyx to match util.py addon_dir fix.
Fix platform detection of OSX ('darwin')
Merge pull request #10 from jasperges/master

Fix platform detection of OSX ('darwin')
Removed cwd = render_output from render.py