mysql: install headers in subdirectory

Closes #21674.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
mysql 5.6.14

 - update patch
 - make cmake more verbose
 - update install paths to be relative

Closes #24352.
mysql 5.6.14 bottles
llvm: install all tools, make keg-only.

Closes #24263.
mysql: modernize style, add compilation comment
mariadb: port changes from mysql formula and modernize style
percona-server: port changes from mysql formula and modernize style
mysql/percona: remove readline cruft

It does not appear to be possible to make mysql or percona link against
GNU readline anymore, since mysql stopped bundling it.
pypy: unset PYTHONPATH while building

Fixes #24364.
Box2D v2.3.0

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
gcutil 1.11.0

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
libtorrent-rasterbar 0.16.12

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
msktutil 0.5.1

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
authexec: compile manually to avoid universal build
dmtx-utils: add pkg-config dep
ezstream: add pkg-config dep
libxspf: fix build under superenv
sispmctl: fix dependency
ETL 0.04.17
python: remove outdated patch

Fixes #24366.