'PlugIns' is normal for MacOS and whatever is generating qt.conf
(macdeployqt?) is using 'PlugIns', so this both builds and generates
an app that works on case insensitive filesystems but fails to load
on case sensitive filesystems.
I haven't tested building the installer, only modifying the
qt.conf in the installed copy of OBS.app.
Fixes https://github.com/obsproject/obs-studio/issues/2302
The current scripting directory path given to Python on OSX is
`../data/obs-scripting`. This works when bin/ and data/ are in the same
folder like rundir after a compile and in the old .app bundles but the
new normal .app bundle structure is different.
For bundles move obspython.py and _obspython.so to the binary folder,
just like the Lua one, and pass that bin path to the Python interpreter
so it can find it.
The current working dir isn't guaranteed to be set with .app bundles
so look up binary path at runtime.
