ASSTags: remove support for using "friendly" tag names, such as "\pos" in function parameters that expect a tag name; to replace this functionality, ASSFoundation:getTagNames() was added, which takes a friendly tag name and return a list of internal tag names, which can be used in function parameters that expect tag names. This change was necessary, because multiple internal tag names may be mapped to a single friendly tag name (such as "\move" or "\clip").