help: adding a new help topic about extensions
Currently listing non-enabled extensions and a short introductory text.
Thanks to Dan Villiom Podlaski Christiansen for the preliminary
proof-of-concept code for listing available extensions.
Matt Mackall <mpm@selenic.com> [Sat, 20 Jun 2009 16:42:51 -0500] rev 8862
bookmarks: add appropriate locking (issue1691)
- make updates of bookmark state locked and atomic
- wrap commit so that commit and bookmarks happen under the same lock