renderArea getter
Merge branch 'protected' into renderAreaGetter

Conflicts:
	src/drawers/abstractDrawer.ts
renderArea now public protected
Merge branch 'protected' into renderAreaGetter

Conflicts:
	src/drawers/elementDrawer.ts
Merge pull request #1430 from palantir/renderAreaGetter

[Drawer] - renderArea getter
Merge branch 'protected' into protectedDrawer

Conflicts:
	plottable.d.ts
	src/drawers/abstractDrawer.ts