Merge branch 'release/0.8.7' into develop
Yaxis changes from Jin
Brush changes from Jin
Add util function for determine when dual axis should/is/will be visible. Dual limit is context attribute and exposed via getter/setter.
Second yAxis
Line has axis index attribute. Fix axis transform
Add prepareCanvas function to toggle right border when dual axes are activated
Draw on second axis
Rename index to version. Remove cruft. Reset line state between draws. Indicate axis on legend.
Update test app to match quandl short codes
Add dual yaxes values as arguments. Add title attribtue and argument to context.
Remove unfinished test
Add camelize util function. extractArguments revised to call function with camelized attr name. Arguments, attributes, options separated.
Use correct scale for drawing points
Calculate extents once for each draw
If user provided y axes values are invalid, ignore them
Remove cruft. Add check for flat lines.
Add Stage attributes to expose visible lines (as array on indicies). Update when toggle event fired.
Add context attribute allowTooltip. Allow override via args to disable stage tooltip
Stage user context values for start aned end date if set. Add context functions to allow setting via arguments