[racket] Whalesong 1.8 released

Hi everyone,


This release addresses some bugs:

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Bugs fixed:

 * appcache manifests did not allow for external network communication.

 * --compress-javascript didn't work under certain situations in 1.7.

 * view-up, view-down, view-left, view-right produced bad error
messages without trace when illegal movement occurred.

 * view-append-child produced a bad error message when trying to
append to a non-element.

 * applying a non-procedure produced the wrong error message
("closure"s instead of "procedure"s)


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To upgrade, just delete the old launcher and create a new one
according to the documentation in:

   http://hashcollision.org/whalesong