Updates based on conversations at PyCon

* Align PPC Electors with PSF voting members as described in the PSF bylaws.  Rather than the previous
  categories, this approach is generally deemed to be both equitable and workable.
* Update the mechanics and timeline of PPC elections, into three phases: self-selection of Electors,
  nominations of Council members, voting
* Remove the language around initial membership and adding a new member, as these are no longer necessary.
* Add language about the call for deanonymization of ballots in cases where foul play is suspected.
* Clarify the PSC's role in approving changes to this PEP, and responsibilities in certain corner cases of the
  election process.
* Explicitly disallow PSC members from concurrently serving on the PPC.
* Clarify language around the expectation of the PSC and PSF to adjust existing standing delegations
* Unify language around "Packaging Council Electors" rather than "voting members"
* Added an acknowledgments section
* Various spelling, grammar, and wording fixes

Author: warsaw