[plt-dev] Release Announcement for v4.2.1

The release announcement item candidates that I have so far are below.
Please mail me new items and/or edits.

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[Matthew]
* fixed problem with installation of docs in planet packages
  (adjust planet client to handle nested planet invocations by
  re-building the doc index only once)
* delete/backspace issue in DrScheme/MrEd
* identifier-prune-lexical-context (4.2.0.2)
  syntax-local-lift-values-expression (4.2.0.3)
  syntax-local-lift-provide
* safe-for-space fixes for the interepreter
* expose and support unreadable symbols
* Various efficiency improvements to keyword arguments.
* better interaction of HtDP languages with scheme/match

[Jay]
* FrTime reorganization

[Matthias]
* new universe teachpack updates?
  (universe keeps track of iworlds now; utest contains ball game)

[Robby]
* redex stuff (brought back syntax locations (for better error
  messages) in redex main forms and improved define-relation;
  improved where patterns and a few bug fixes; added
  metafunction-cases and fixed a layout bug; fixed bug in
  rendering of reduction relations; added x-spacing and y-spacing
  parameters to traces and traces/ps)
* DrScheme's module browser always shows files from the same
  collection (possibly a planet collection) regardless of the kind
  of `require' form that is used.

[Ryan]
* macro-debugger stuff (disable lift errors; fixed opaque variable
  ref bug)
* syntax/parse and syntax/id-table libraries

[Sam]
* typed-scheme stuff ("paths branch")

[Eli]
* New `make-at-reader/inside' and `make-at-reader' makes it easy
  to define new scribble readers (in "inside mode" or not) with a
  command character different from `@'.
* Note about one of the last builds to include a solaris
  distribution, and if anyone has access to a solaris machine we
  can incorporate it into the build.

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-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!