Remove the Abstract module. Rename every abstract class as follows:

Abstract.X -> X.AbstractX
e.g.
Abstract.Plot -> Plot.AbstractPlot

The exception:
Abstract.PlottableObject -> Core.PlottableObject
Rename files so fileName == className.moduleName
Fix reference.ts
Address Bluong's concerns
Merge branch 'api-breaks' into remove-abstract

Conflicts:
	plottable-dev.d.ts
	plottable.d.ts
	plottable.js
	src/components/plots/abstractPlot.ts
Merge pull request #1171 from palantir/remove-abstract

Remove abstract module