copy edits and profile page title

common/static/common/js/discussion/utils.js

...atic/common/js/discussion/views/discussion_inline_view.js

...common/js/discussion/views/discussion_thread_list_view.js

...atic/common/js/discussion/views/discussion_thread_view.js

...tatic/common/js/discussion/views/response_comment_view.js

...cussion/templates/discussion/discussion_profile_page.html

lms/static/sass/discussion/_layouts.scss