Update our mono to a modern version. The one in ports currently is an
early release of the 5.x branch and is very buggy. I see lots of crashes
that never used to happen with 4.8.
This version builds and packages and is using BoringSSL
TODO:
* Enable jemalloc from base if possible
* Tests?
* Figure out if any of the old patches from D14006 are worth keeping
** I removed all of those patches after conferring with the guy who
ported Mono to AIX recently and something in there was also causing
build failures.
Also he strongly recommends against us trying to make "freebsd" verb a
supported platform. Even his AIX builds piggyback on the "linux" verb.
It seems to cause needless complexity. (I might be using wrong
terminology here; I don't grok build frameworks very well)
I also have a patch that fixes an issue with freebsd building with a
newer version of corefx, but that seems to only occur if we try to build
mono HEAD.