2.0.0-RC3

• Fixes issues in cmta studentify and cmta linearize with proper handling of pre-existing artifacts
• Unifies handling of CMT settings cmt.test-code-folders and cmt.read-me-files. These list of files and folders are handled in exactly the same way when moving between exercises (e.g. by executing cmtc next-exercise). Both handle folders and individual files. cmta and cmtc will issue a warning when the aforementioned settings have elements that have a prefix that is already in the settings on its own.