log: resolve --follow with -rREV in cmdutil.getlogrevs()
This also fixes alias expansion. Before, reverse() could be overridden by user
alias.
This isn't processed at _logrevs() as we'll need starting revisions to parse
file patterns. See the subsequent patches for details.
{
"conduit_uri": "https://phab.mercurial-scm.org/api",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}