Merge pull request #1416 from edx/dhm/regex_courseid

cms/djangoapps/contentstore/tests/test_course_index.py

cms/djangoapps/contentstore/views/course.py

cms/djangoapps/contentstore/views/user.py

cms/templates/widgets/header.html

cms/urls.py

common/lib/xmodule/xmodule/modulestore/exceptions.py

common/lib/xmodule/xmodule/modulestore/locator.py

common/lib/xmodule/xmodule/modulestore/parsers.py

common/lib/xmodule/xmodule/modulestore/split_mongo/split.py

...xmodule/xmodule/modulestore/tests/test_location_mapper.py

...on/lib/xmodule/xmodule/modulestore/tests/test_locators.py