Merge pull request #2 from peacedove/master

Update Sankey function
Refactored selectCourse to pathVizService
Revised bubble group style.
Added course info view/controller
Added bar chart
Added bar chart into course info
Update TODO
Separated course info view from coursePath
Rename course to courseInfo
Refactored svgCoords2Path
coursePath: reuse bubble chart
Added alumnus view in bubble chart
Updated TODO
Revised bubble chart pointer style
pvService: updated comment