gobject-introspection: update 1.42.0 bottle.
libgcrypt: update 1.6.2 bottle.
libidn: update 1.29 bottle.
libsndfile: update 1.0.25 bottle.
libusb: update 1.0.19 bottle.
libusb-compat: update 0.1.5 bottle.
lua: add 5.2.3_1 bottle.
mad: update 0.15.1b bottle.
objective-caml: update 4.01.0_1 bottle.
pango: update 1.36.8 bottle.
popt: update 1.16 bottle.
proj: update 4.8.0 bottle.
python3: update 3.4.2_1 bottle.
scons: update 2.3.4 bottle.
sdl: update 1.2.15 bottle.
yasm: update 1.3.0 bottle.
gnutls 3.3.9

“I’ve just [released gnutls 3.3.9](http://article.gmane.org/gmane.comp.encryption.gpg.gnutls.devel/7728). This is a bug-fix release on the stable branch. With this release the 3.3.x branch becomes the stable branch.”
gnutls: update 3.3.9 bottle.

Closes #33288.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
doctor: clarify 10.10 Xcode situation.
libinfinity 0.6.4

Version bump. Please don’t merge this before #33288 goes in.