Enhance Course content to include microcourse title as a field

Currently, a subsite/course has a title - see get_blog_details($site_id)->blogname, and a path (which includes, by our convention, the short course code or "tag") get_blog_details($site_id)->pathinfo (the actual course code is extracted via "function get_site_tag($site)"). The problem is that a "Course" in OERu's context has 3 bits of important information: an overarching course title, e.g. "Learning in a Digital Age", which is comprised of a few microcourses, each with a title, like "Digital literacies for online learning" (lida101), or "Digital Citizenship" (lida102), or "Open education, copyright and open licensing in a digital world" (lida103), etc. These microcourse titles are currently not represented in metadata, only as a title field in the curriculum materials.

Ideally, we should store the Course Title, and component Microcourse Titles (with their course code) separately, and those should in turn, inform the curriculum material fields and path information, not the other way around.