error logging on ws api calls.
added interpreted to worksheet call to get print version.
base worksheet with react

Tables currently work and markdown.

Table info still needs
lookup_targets
Merge branch 'refs/heads/upstream/master' into upstream/feature/worksheet_interface

Conflicts:
	codalab/apps/web/static/codalab.min.map
render $$ x $$ into basic mathjax
added link to bundle page and fixed / at ulrs
Some style improvements for worksheet detail
Convert bundle detail view from Angular to React
Better syntax
Use for…in to make iteration more efficient
Simplify bundle detail markup, adjust css for new markup
Abstract out new table styling
Bundle and worksheet loading gifs
Merge pull request #598 from codalab/feature/bundle_detail

Bundle detail page, some style improvements for worksheet detail
refactor and add worksheet content  manager
Basic bundle download

 Only works on single files, and returns wrong content type. but you can click download and see your image or single file.

issue #490
Keyboard shortuts, event binding framework

As implemented, j and k change the boolean prop "focused" on worksheet items.
Merge pull request #601 from codalab/feature/keyboard_shortcuts

Keyboard shortuts, event binding framework
Merge branch 'refs/heads/upstream/master' into upstream/feature/worksheet_interface

Conflicts:
	codalab/apps/web/static/codalab.min.map
Make window scroll with focused worksheet item; add ability to toggle keyboard shortcuts on/off while maintaining focusIndex