[PATCH] Separate SSL error detail name and message

Currently, SSL error detail in Squid-generated error pages (%D) contains
both the error name and the explanation text.

Some folks using this feature want to render the two pieces of
information differently because the error name is not something most
end-users should read or focus on.

This patch adds the "%x" error page formating code which prints the
error name, and removes the error name (%err_name) from SSL error detail
messages.

This is a Measurement Factory project