[plt-planet-announce] Updated PLaneT package: dyoo/whalesong.plt for 4.x

This announces the availability of an updated package from PLaneT:

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Name:            whalesong.plt
Package version: 1.7
Owner:           dyoo


Package Description
A Racket to JavaScript compiler
Release Notes

Added primitives: hash-keys, hash-values, hash-for-each, hash-map, write. Merges some changes to support sk's cs019 language level.

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Go to 

http://planet.racket-lang.org/display.ss?package=whalesong.plt&owner=dyoo

for more information.