google-app-engine: 1.8.1.

Closes #20438
install: remove overcautious array manipulation
rust: fix test (cargo is no longer)
libxml2: Fix missing option --with-python

Fixes #20426
Add pkg-config files for 10.9

Seems to be that 10.9 needs the same ones as 10.8.

Fixes #20436.
glib 2.36.3
ispc: fix audit
libvirt: Add python bindings (:recommended)

With the new python dependency support in Homebrew, libvirt can now
build Python bindings.

Closes #20311.

Signed-off-by: Samuel John <github@SamuelJohn.de>
libvirt: Adding a test
libvirt: typo in --without-python option