paper: define searchhint message in map file and use it in other templates
paper: edit search hint to include new feature description
pull: for pull --update with failed update, print hint if any

An upcoming patch will add a hint to the abort message, and we don't want to
lose that here.
update: improve error message for clean non-linear update
update: add error message for dirty non-linear update with no rev

Previously, the error message for a dirty non-linear update was the same (and
relatively unhelpful) whether or not a rev was specified. This patch and an
upcoming one will introduce separate, more helpful hints.
update: improve error message for dirty non-linear update with rev
update: standardize error message for dirty update --check

This and following patches will standardize the error message for dirty working
directories to "uncommitted changes".
merge: standardize error message for dirty working dir
merge: standardize error message for dirty subrepo
cmdutil.bailifchanged: standardize error message for dirty working dir

This affects rebase, graft, histedit, and other similar commands.
largefiles: standardize error message for dirty working dir
sslutil: add a config knob to support TLS (default) or SSLv23 (bc) (issue4038)

Prior to this change, we default to SSLv23, which is insecure because
it allows use of SSLv2. Unfortunately, there's no constant for OpenSSL
to let us use SSLv3 or TLS - we have to pick one or the other. We
expose a knob to revert to pre-TLS SSL for the user that has an
ancient server that lacks proper TLS support.
httpclient: import 4bb625347d4a to provide SSL wrapper injection

This lets us inject our own ssl.wrap_socket equivalent into
httpclient, which means that any changes we make to our ssl handling
can be *entirely* on our side without having to muck with httpclient,
which sounds appealing. For example, an extension could wrap
sslutil.ssl_wrap_socket with an api-compatible wrapper and then tweak
SSL settings more precisely or use GnuTLS instead of OpenSSL.
sslutil: make keyfile and certfile arguments consistent between 2.6+ and 2.5-
httpconnection: properly inject ssl_wrap_socket into httpclient (issue4038)

This causes httpclient to use the same SSL settings as the rest of
Mercurial, and adds an easy extension point for later modifications to
our ssl handling.