test: extract develwarn transaction testing in its own command The lack of locking for a transation is about to change from a warning to an error. We first extract the test decidated to this warning to make the next changeset clearer.

graphmod: update edgemap in-place The edgemap update was not actually propagated to future asciiedge calls; update the edge state dictionary in-place instead.

tests: test-archive.t use mercurial.util for urllib compat