extend {{URL}}, rework {{PLAY}} parameters

- new options for {{URL}}: key:dflt:addPath:addOpt to work around the ?
vs & issue
- {{PLAY}} parameters divided into own strings: PlexConnectPlayType,
-RatingKey, -CopyIx to help with “url-ratingKey” in the long run…

Not a big change program-wise, but it affects basically ALL our
templates. :-(