bug#25061: consider adding %COMPAT to default gnutls priority string

[Ted Zlatanov]

On Wed, 20 Dec 2017 20:15:48 -0500 Ted Zlatanov <tzz@lifelogs.com> wrote: 

TZ> On Wed, 20 Dec 2017 18:19:10 +0200 Eli Zaretskii <eliz@gnu.org> wrote: 
EZ> Thanks, but this means Emacs will now refuse to load GnuTLS on systems
EZ> that have version 3.4 or older of the library, right?  If so, I think
EZ> the loading and the use of the function should be conditioned by an
EZ> appropriate preprocessor directive to compile that code only for
EZ> 3.5.X.

TZ> I've applied Andy's updated patch for GnuTLS 3.5.1 and older, and
TZ> hard-coded compatibility for %DUMBFW between 3.2.5 when it was
TZ> introduced and 3.5.1.

TZ> Looking forward to closing this one for good... thanks.

Noah's Travis CI build passed. I'll wait for Andy, Eli, and Kaushal to
confirm before marking this as done.

Ted