make new-∀/c and new-∃/c figure our their own names and have a better printing
add pict->argb-pixels and argb-pixels->pict
Fix subst-all contract.
racket/draw: faster (on some platforms) path for drawing a bitmap

The faster path applies in the common case of drawing a whole
bitmap, as opposed to a section of the bitmap.

Thanks to Laurent Orseau for tracking down this performance issue.
games/cards: add @2x card images

For both original and @2x, adjust images to use alphas for the corner,
instead of drawing with clipping, which avoids alignment problems on
an @2x display.
remove/adjust obsolete C preprocessor cases

Mac OS Classic and Palm ae long since unsupported.

TCP support implies sockets (since old Mac TCP is gone).

For what it's worth, make the build work without TCP support, although
no one ever builds that way.
faster path for TCP input

Avoid polling a file descriptor to determine whether it has bytes;
just try to read, and then go to epoll/kevent mode when available,
skipping a poll/select.
reduce calls to `current-process-milliseconds` on thread swap

Call `current-process-milliseconds` once per swap, instead of twice.
fix bug in insertion of guards to prevent use before definition
fix positive integer generator to not generate zero
add random generation for polymorphic contracts
fix struct/dc's flat-contract mode predicate
Actually fix all of the contract errors in substitute.rkt
scribble: fix HTML scaling of GIFs

Even without scaling, declare the size of a PNG or GIF in HTML
output.
fix angle conversion problem
Fix return tc-results when typechecking kw lambda.
fix mailing list link

closes PR 14491
adjust angle->proper-range based on Neil's advice
Rackety (102 columns)
remove printf