Documentation for static page changes

docs/en_us/course_authors/source/Images/image157.png

docs/en_us/course_authors/source/Images/image161.png

docs/en_us/course_authors/source/Images/page_bar_lms.png

docs/en_us/course_authors/source/Images/pages_editor.png

docs/en_us/course_authors/source/Images/pages_empty.png

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...urse_authors/source/building_course/create_new_course.rst

...e_authors/source/building_course/export_import_course.rst

docs/en_us/course_authors/source/change_log.rst

.../en_us/course_authors/source/getting_started/glossary.rst

.../course_authors/source/problems_tools/google_hangouts.rst