Clean up graphviz building script and meta file.
Update gridmap to 0.12.4
Merge pull request #119 from dan-blanchard/update_gridmap

Update gridmap to 0.12.4
Backport scikit-image recipe from Anaconda
Use the git:// url for scikit-image
Bump build number from 2 to 3.
Merge pull request #118 from yungyuc/graphviz

Clean up graphviz building script and meta file.