cleanup: Remove ports depending on expired lang/gcc6-aux

Keep ports-mgmt/synth and dependencies (including lang/gcc6-aux itself)
for now as synth is the only Ada port still maintained and might be
somewhat high-profile.

Removed ports:
archivers/zip-ada
cad/ghdl
databases/adabase
databases/apq
databases/apq-mysql
databases/apq-odbc
databases/apq-pgsql
devel/ada-util

devel/ada-util: extend BROKENness to FreeBSD 14

Remove # $FreeBSD$ from Makefiles.

Mark BROKEN on FreeBSD 12 and 13

Reported by:	pkg-fallout
MFH:		2019Q2

Bump PORTREVISIONs of all users of math/mpc that we just updated to
version 1.1.0 (via revision 464079).

- Fix plist

Return ports maintained by John Marino to the pool, he is no longer interested.

Submitted by:	Mark Millard via private e-mail

Return the ports mistakenly reset to ports@ in r433856 to John Marino.

The mistake was completely on my part, I somehow connected the dots the
wrong way in my head.

The only exceptions (for now) are archivers/zstd and ports-mgmt/synth
which were already picked up by new volunteers in the mean time.

Return ports maintained by John Marino to the pool, see r433827 for details

Change Ada Framework foundation from gcc5-aux to gcc6-aux

GCC 6.1 was released this week.  The Ada Framework in FreeBSD ports has
been based on GCC 5.3 GNAT although GCC 6.x has been supported for awhile
via the ADA_DEFAULT option in make.conf.

Now that GCC 6 has been officially released, switch to it by default.
People can maintain the old foundation by putting "ADA_DEFAULT=5" in
/etc/make.conf.

Libraries built by one GNAT are unusable by another, so almost every Ada
port has been bumped as a result.  Noticable exceptions are dns/ironsides
which fails to build on gcc6 (thus USES=ada:5 is set) and cad/ghdl which
needs additional testing as it may require gcc5 on FreeBSD (DragonFly
uses the LLVM backend only).

Remove ${PORTSDIR}/ from dependencies, categories d, e, f, and g.

With hat:	portmgr
Sponsored by:	Absolight

devel/ada-util: Add many missing source files, remove xmlada support

I have my doubts about gprinstall.  It missed installing many source
files.  I can only assume it's buggy.  Scoop them up in a crude fashion
with post-install target.

While here, turn off xmlada support.  The configure script in this are
is hopelessly broken (it doesn't want to accept no for an answer) so
just rip out the configure script guts.  XML/Ada is GPL and it will
carry the license to any project that uses Ada-util.  It also makes
XML/Ada a run dependency for the same project.  Probably in the future
I will return support in form of a non-default option, but I'll want
up to a more recent version.

devel/ada-util: Quiet down hardcoded loggers

Loggers are hardcoded for several packages at the INFO level which is
quite useless for things like spawning commands.  It is too chatty!
Set the loggers to filter out everything up less than ERROR messages.

Add new port: devel/ada-util (Ada Utility Library)

This Ada05 library contains various utility packages for building
Ada05 applications.  This includes:

 o A logging framework close to Java log4j framework
 o Support for properties
 o A serialization/deserialization framework for XML, JSON, CSV
 o Ada beans framework
 o Encoding/decoding framework (Base16, Base64, SHA, HMAC-SHA)
 o A composing stream framework (raw, files, buffers, pipes, sockets)
 o Several concurrency tools (reference counters, counters, pools,
   fifos, arrays)
 o Process creation and pipes
 o Support for loading shared libraries (on Windows or Unix)
 o HTTP client library on top of CURL or AWS

Ada Util also provides a small test utility library on top of
Ahven to help in writing unit tests.