Fix for #16455

This reverts 5fdd86, which introduced a self-referential dictionary-- which mean that it could never be garbage collected.
Wrap the split modules in objects, so we can avoid the attr/value ordering problem
Move to use lambda, to keep pylint happy
Minor wording fix in highstate docs

This fixes some grammar weirdness.
Merge remote-tracking branch 'upstream/pr/16557' into 2014.7
No need to check if process is alive. Fixes #16487. Refs #16317.

There's no need to check for a live process because since we're changing flags on the file descriptor, if it's not none, we
reset the flags.
Merge pull request #16569 from s0undt3ch/hotfix/vt-freezes-on-osx

No need to check if process is alive. Fixes #16487. Refs #16317.
Merge pull request #16566 from terminalmage/docs

Minor wording fix in highstate docs
Set the cachedir to a relative path
Set the cachedir to a relative path
Set the cachedir to a relative path
Set the cachedir to a relative path
Fix ensure in syspath call