Loop over taus in stat_quantile.
Fixes #188.  Also general tidy up of code and improved examples
stat_quantile: Add try_require for MatrixModels when using rqss
stat_quantile: documentation tweak
Update NEWS
Merge branch 'quantile-fixes'
scale_size_area: default to area proportional to data value
Re-roxygenize
Merge branch 'area-scale'

Fixes #635.
Move staticdocs/ to inst/staticdocs/

This move is so that a built package will contain the staticdocs content.
The staticdocs package has been updated to search in pkgdir/inst/staticdocs/ as
well as pkgdir/staticdocs/.
Update NEWS
Update stat_bin message
element_text: add check for missing angle.

Fixes #658
Fix previous commit for element_text and empty angle
dist_polar: don't error on NA values
Update NEWS
Add NaN to polar distance test
Add devel version number to NEWS
Fixes for new version of plyr
put subclass first for class attributes of subclasses of element
theme docs: added more explanation of plot.margin