support category subpositions and hover tool on rectangles with catagorical coords
add hover tool to categorical heatmap
Merge branch 'master' of github.com:ContinuumIO/bokeh
Merge branch 'master' of github.com:ContinuumIO/bokeh
Merge branch 'master' of github.com:ContinuumIO/bokeh
add .gitignore
make color tooltip more robust against missing data
Merge branch 'master' of github.com:ContinuumIO/bokeh
handle no dash case