util: add progress callback support to copyfiles

revert: evaluate filesets against working directory (issue4497) As the failing revert tests in test-fileset-generated.t show, Revert currently creates one matcher for matching files in the working copy and another matcher for matching files in the target revision. The two matchers are created with different contexts, which means filesets are evaluated differently. Then the union of the sets of files matching the matchers in the two contexts are reverted. It doesn't seem to make sense to use two different matchers; only the context they're applied to should be different. It seems very likely that the user wants the filesets to be evaluated against the working directory, which the tests test-fileset-generated.t also assume, so let's make it so. I willingly admit that the largefiles code was modified by trial and error (according to tests).

largefiles: extract and reuse 'standin' variable in overriderevert()

largefiles: override cmdutil.revert() instead of comands.revert() By overriding the cmdutil method we don't need to override both the function and the command. Also, we get access to the 'ctx' and 'parents' variables, which will soon prove useful. Rename the 'ctx' argument to overridematch() to 'mctx' rather than letting it shadow new 'ctx'.