WIP refactor limelight graph stuff
WIP refactor limelight graph continued
Merge branch 'master' into wip-refactor-graph-stuff

Conflicts:
	app/assets/javascripts/extensions/views/graph/graph.js
	app/assets/javascripts/extensions/views/graph/line.js
	app/assets/javascripts/extensions/views/graph/stack.js
	app/assets/javascripts/extensions/views/graph/stackedbar.js
	app/assets/javascripts/extensions/views/timeseries-graph/line.js
	app/assets/javascripts/extensions/views/timeseries-graph/stack.js
	app/assets/javascripts/extensions/views/timeseries-graph/timeseries-graph.js
fix tests
tidy up / centralise tests
simplify graph inheritance
fix stackedbar component
Merge pull request #150 from alphagov/wip-refactor-graph-stuff

Refactor graphs