open-mpi: still fails check with clang 425

Closes #21701
chromedriver 2.2

Closes #21743.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
glib 2.36.4
pixman 0.30.2
gpgme 1.4.2
cmake: Added --HEAD
python_helper prepends PYTHONPATH

…instead of appending. This should be safer against any
malformed user-defined values in the PYTHONPATH.
For brewed python, make sure to unset the PYTHONPATH

during building of python software inside of a `python do … end` block.
Python: Exit if PYTHONPATH is wrong

In our sitecustomize.py we instruct python to exit with an error message
if the PYTHONPATH is pointing to a wrong homebrew site-packages dir.
With wrong meaning another major python version.

If you set the PYTHONPATH to include
    $(brew --prefix)/lib/python2.7/site-packages
and start python3, it may pick up modules from there, wich can result
in errors for non pure python modules (such as PyQt).
Improve docs for Formula#python (python_helper)
Don't hard-code PYTHONPATH for `brew test`

This rules out any possibility to test Python 3.x software as the
PYTHONPATH is used by any Python and `brew test pyqt --with-python3`
fails because it picks up the `pyqt` module fomr Python 2.x's
site-packages. Upstream tells us not to set the PYTHONPATH and then
starting another (major) python version.
sip: We don't need sip and sip3 binaries

They are both identical. Difference lies in the config and libs.
qt: Default to build in-place and preserve the src

Needed for debug symbols.
PySide needs the source for documentation generation.
Closes #20020
qt: typo
qt: Fix Framework symlinks

doh.
qt5: Default to build in-place and preserve the src

Needed for debug symbols.
PySide needs the source for documentation generation.
Closes #20020
shiboken: 1.2.0, fix tests, run tests, add --HEAD
python: setuptools 0.9.8
python3: setuptools 0.9.8
python: Harden build by unsetting PYTHONPATH