Another potential deparse issue
Better errors when retrieving from the object store
More flexible use of maker environents

Getting access to the functions is going to be important, so
having this as a core maker function is required.  m$environment() returns
an environment that can be attached with maker_attach (dropping the
_environment from that function).
Remove unnecessarily convoluted logic around verbosity

Always print READ when loading sources, move checking about
verbose into print_message rather than around uses of
print_message.