Also move NEWS item to correct position (it was in 3.3).

Also applies to cherry pick Issue #20909.

Since Victor linked to it in a block, it seems to make sense to have
all the SSLContext changes next to each other.  I also sorted all the
SSL security enhancements next to each other in the security
enhancements summary.

When running external programs such as a C compiler and getting an
error code, distutils only prints the program name.  With this change,
one can get the full command line by setting the DISTUTILS_DEBUG
environment variable.

This should have no compatibility issues, unless there are tools
that depend on the exact format of distutils debug messages.

Patch by Anastasia Filatova.

Patch by Tshepang Lekhonkhobe, reviewed by Georg Brandl.

Patch by Sean Rodman.

- based on pip and other PyPA tools
- includes references to the new Python Packaging User Guide
  where appropriate (and the relevant section is at least
  partially filled in)
- started new FAQ sections
- both guides aim to introduce users to basic open source
  concepts if they aren't aware of them
- existing guides have been relocated (now linked from the
  distutils docs) rather then removed, since there is
  some needed material that has yet to be relocated to the
  distutils docs as a reference for the legacy formats

It's not exact, but easier to understand.