refactor options from cmdtable
- add extracommitopts for user and date
- factor stuff
raise util.Abort again if specified revision is not an integer.
This was changed to NoRepo in
462cc56d898f, because specifying non-integer
revisions for e.g. the Mercurial backend caused Abort to be raised in the
subversion importer.
Now util.Abort is raised again, but the check is done after verifying if it
really is a subversion repository.
Replace _ with inst for catching exceptions to not shadow gettext.
And removed one _(...) because mercurial.i18n is not yet imported
in convert/subversion.py.