[PATCH] rebase: clarify --source and --base documentation so it's less ambiguous

[Augie Fackler]

# HG changeset patch
# User Augie Fackler <raf at durin42.com>
# Date 1412026314 14400
#      Mon Sep 29 17:31:54 2014 -0400
# Node ID 205bd6e5778956a22663ec1d81542c6bcdd40522
# Parent  a1eb21f5caea4366310e32aa85248791d5bbfa0c
rebase: clarify --source and --base documentation so it's less ambiguous

I've been burned by these descriptions before, and others have as
well. Hopefully this is more universally understandable.

diff --git a/hgext/rebase.py b/hgext/rebase.py
--- a/hgext/rebase.py
+++ b/hgext/rebase.py
@@ -50,10 +50,10 @@
 
 @command('rebase',
     [('s', 'source', '',
-     _('rebase from the specified changeset'), _('REV')),
+     _('rebase the specified changeset and its descendants'), _('REV')),
     ('b', 'base', '',
-     _('rebase the tree around the specified changeset without '
-       'ancestors of dest'),
+     _('rebase specified changeset and all ancestors which are not already'
+       ' ancestors of the destination'),
      _('REV')),
     ('r', 'rev', [],
      _('rebase these revisions'),