checkheads: pass "ispushed" function to the obsmarkers logic We are about to make "allfuturecommon" a set of revs instead of a set of nodes. The function updated in this patch do not needs to know about these details so we just pass it a 'ispushed(node)' function. This will simplify the next changeset.

profile: drop maybeprofile It seems sufficiently simple to use "profile(enabled=X)" to not justify having a dedicated context manager just to read the config. (I do not have a too strong opinion about this).

profile: support --profile in alias and abbreviated version (--prof) We now process the "--profile" a second time after alias has been processed and the command argument fully parsed. If appropriate we enable profiling at that time. In these situation, the --profile will cover less than if the full --profile flag was passed on the command line. This is better than the previous behavior (flag ignored) and still fullfil multiple valid usecases.