Merge pull request #442 from edx/felix/formula-hints

common/lib/capa/capa/responsetypes.py

common/lib/capa/capa/tests/test_responsetypes.py

common/lib/xmodule/xmodule/crowdsource_hinter.py

...n/lib/xmodule/xmodule/css/crowdsource_hinter/display.scss

...n/lib/xmodule/xmodule/js/fixtures/crowdsource_hinter.html

common/lib/xmodule/xmodule/js/spec/capa/display_spec.coffee

...le/xmodule/js/spec/crowdsource_hinter/display_spec.coffee

common/lib/xmodule/xmodule/js/src/capa/display.coffee

.../xmodule/xmodule/js/src/crowdsource_hinter/display.coffee

common/lib/xmodule/xmodule/tests/test_crowdsource_hinter.py

common/templates/hinter_display.html

lms/djangoapps/instructor/hint_manager.py

lms/djangoapps/instructor/tests/test_hint_manager.py

lms/templates/instructor/hint_manager.html

lms/templates/instructor/hint_manager_inner.html