Improved coloring of scatterplots (for eventual composite graph support)
Legend highlighting support for composited scatterplots
Scatterplot brushing and support for points with the same y-value
Scatterplot highlighting for rectangular brushed areas
Composite chart brushing delegates filtering to child charts
test decreasing composite brush extent
currently broken (failing test when mixing differnt charts in composite)
Fixed legends of composite charts with scatterplot subcharts
Fixed filtering of composite chart subcharts when subcharts have differing filter types
Pointed grunt-contrib-jasmine to existing branch
Scatter plot refactorings and improvements using suggestions from jrideout
Merge pull request #437, fix conflict and lint

Conflicts:
	src/line-chart.js
add series example with scatterPlot
Fixed null filtering on heatmaps + removed empty test file
Merge pull request #446
Merge pull request #443
Merge pull request #1 from NickQiZhu/master

rebasing my fork