scmutil: improve documentation of writereporequirements() This makes it easier to understand the difference between `writerequires()` and `writereporequirements()`. Differential Revision: https://phab.mercurial-scm.org/D9568

command: automatically create alias for command using '-' in names As discussed during the "5.6 Sprint" ignoring dash in command name open the way to using them more. We can now move existing command to more readable (dash using) names without breaking any compatibility. Differential Revision: https://phab.mercurial-scm.org/D9515