util: move dirs() and finddirs() from scmutil to util An upcoming commit requires that match.py be able to call scmutil.dirs(), but when match.py imports scmutil, a dependency cycle is created. This commit avoids the cycle by moving dirs() and its related finddirs() function from scmutil to util, which match.py already depends on.

parsers: remove unused dependency on util Parsers.py had a reference to util.sha1 which was unused. This commit removes this reference as well as the unused import of util to simplify the dependency graph. This is important for the next commit which actually relocates part of a module to eliminate a cycle.

changectx.walk: drop unnecessary call to match function If all the files in match.files() are in the context/manifest, we already know that the matcher will match each file.