add back 'orientation' in type: 'histogram'
add 'histfunc' to 'histogram', 'histogram2d' & 'histogram2dcontour'
add to 2d arrays to val types in 'scatter3d.{x,y,z}' & 'surface.{x,y}'
rm unnecessary '/' in link
correct 'error.{x,y,z}arrayminus' val type
fix typo
make run
fix ambiguity in histnorm and histfunc val types
improve 'histfunc' description
Merge pull request #28 from plotly/etienne-misc-fixes

Etienne misc fixes