racket/draw: fix problem with text drawing and scale

Track the transformation of a text-drawing context and reset it
when the current transform changes.

There was already an update on an existing layout for a given
character, but not an update for the context used to create layouts.

Merge to v6.0
Fix typoed character ranges (A-z => A-Z)

Signed-off-by: James McCoy <vega.james@gmail.com>

Merge to v6.0
net/http-client: fix `http-conn-live?` result

Merge to v6.0
Synch German string constants with latest.
fix a synchronization problem in the GC for places

When a GC is needed for the shared space, a GC is triggered
in all places, and the places wait until each other place
has completed. However, the places also need to wait until
all other places are ready to *start* a GC; otherwise, a
place may be modifying a shared record while some other place
traverses it for a GC.

Closes PR 14229

Merge to v6.0
Add more documentation for `Procedure` type

Please merge to v6.0
Describe how to make packages compatible with 5.3.5 and 5.3.6.

As requested by Sam Tobin-Hochstadt on the mailing list today.

Merge to v6.0
Remove extraneous compile of non existent file.

Merge to v6.0
* Parameterized comment-reader over 'unsyntax, for use with RACKETBLOCK
  pkgs/scribble-pkgs/scribble-lib/scribble/comment-reader.rkt
* Updated manual to explain #:escape-id parameter to comment-reader
  pkgs/scribble-pkgs/scribble-doc/scribblings/scribble/manual.scrbl
* Changed parameter name to #:escape-id.
  pkgs/scribble-pkgs/scribble-lib/scribble/comment-reader.rkt
* Changed parsing for #:escape-id to use a peeking-input-port.
  pkgs/scribble-pkgs/scribble-lib/scribble/comment-reader.rkt
scribble/comment-reader doc tweaks
Add n-ary cartesian-product to unstable/list.
Fixed bug 14177

bezout-binary did not handle negative numbers correctly.
Fixed a few errors caught by Pierpaolo.
Make type of expt more precise on floats.

Closes PR14228.
Fix types for `remove` and friends.

A few of these had unnecessary uses of type variables.
The type for `remove*` was unsound.

Please merge to v6.0
Remove unused type variable.
Document version exceptions.
fix bug in number rendering