Add in BaseAxis to act as an ancestor to NumberAxis and CategoryAxis.

Has some core functionality, and draws baseline and tick marks.
Add/clean up JSDoc, remove subclass-specific call from BaseAxis.

Fix incorrect change in CSS.
Remove NumberAxis from commit.
Un-error the build
Have travis run only node 0.10.0
Factor out tick mark and baseline attribute logic

So subclasses can access the results of that logic.
Removed _requestedSpace from baseAxis, streamlined _doRender.
Merge branch 'master' into base-axis
Remove maximumWidth and maximumHeight calls for API consistency.
Merge branch 'master' into base-axis

Conflicts:
	plottable.d.ts
	plottable.js
Add tests.
Actually add the baseAxisTest file.
Fix test error.
Merge pull request #481 from palantir/base-axis

Add in BaseAxis to act as an ancestor to NumberAxis and CategoryAxis.