Use bundled type classes for ghost ownership.
* These type classes bundle an identifier into the global CMRA with a proof that the identifier points to the correct CMRA. Bundling allows us to get rid of many arguments everywhere. * I have setup the type classes so that we no longer have to keep track of the global CMRA identifiers. These are implicit and resolved automatically. * For heap I am also bundling the name of the heap RA instance. There always should be at most one heap instance so this does not introduce ambiguities. * We now have a "maps to" notation!