#673 search bar fetch autocomplete

- update select2 plugin
- search bar functions in two parts: first, type command. Then choose from the returned list of objects
- initial list of commands is static, populated from global var. After command is chosen, ajax call gets list of objects for autocomplete from api
- currently it's being faked with the worksheets api
#673 reset to initial commands

- if the user goes back to an empty search input, reset the options to the initial commands
#673 clean up and refactor

- move non-select2 functionality into ws_actions
- maintain command dictionary in a format that makes sense
- add a method to transform that dictionary into something select2 easily understands
- update executeCommands method to look up its function in the command dict
- add comments
- cosmetic fixes to select2 spinner and outline color
Stub/fake info command

- redirects to worksheet page (instead of bundle details) for now
Clean up comments
search bundle api

issue #673
Click to focus on search bar
Merge branch 'feature/673-add-bundle-ui' of github.com:codalab/codalab into feature/673-add-bundle-ui
#673 hook up real bundle search api
#673 info + bundle goes to bundle detail page
#673 add 'execute' button to search bar
#673 consolidate functionality

- get rid of select2searchmixin
- move functionality into WorksheetSearch component
#673 send search_string to ajax request
#673 added some console logging
#673 add wnew command

- forked select2 to allow minimumInputLength to be a function b/c it has to be changed dynamically
- added 'type' param (get/post) for commands
#673 press 'b' to show/hide searchbar

- doesn't work when searchbar is active or focused
moved search to own file.
forgot to commit <script tag also linter clean up.
always show bar and spacing in code.
Merge branch 'refs/heads/upstream/feature/worksheet_interface' into feature/673-add-bundle-ui

Conflicts:
	codalab/apps/web/static/js/worksheet/worksheet_interface.js