dispatch: add shell aliases
This patch adds git-style "shell aliases" to Mercurial.
Any alias with a definition beginning with a '!' will be treated as a shell
alias. For example:
[alias]
echo = !echo
qempty = !hg qrefresh -X "`hg root`" ; echo Emptied patch "`hg qtop`"
$ hg echo foo
foo
$ hg qempty
Emptied patch foo
$
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 4 changes to 4 files
updating to branch default
4 files updated, 0 files merged, 0 files removed, 0 files unresolved