added some commenting to make use of generic functions a bit less obscure.
Merge remote-tracking branch 'remotes/origin/master' into ci
Made access failure an error condition on glob matching.

When the users is trying to copy a file that they don't have access
to and error is raise.  The standard for 'glob' is to just ignore that
member. cp (under Linux) raises an error but continues, likely we should
try and mimic that behaviour.  TBD.