Close #843. Fix minor issue with racket install

toolset/setup/linux/languages/racket.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 
-RET1=$(fw_exists racket-src/bin/racket)
-RET2=$(fw_exists racket-src/collects/racket)
+RET1=$(fw_exists racket/bin/racket)
+RET2=$(fw_exists racket/collects/racket)
 if [ "$RET1" == 0 ] && [ "$RET2" == 0 ]; then 
   return 0;
 fi

toolset/setup/linux/languages/urweb.sh

@@ -3,9 +3,9 @@
 RETCODE=$(fw_exists /usr/local/bin/urweb)
 [ ! "$RETCODE" == 0 ] || { return 0; }
 
-hg clone http://hg.impredicative.com/urweb
-cd urweb
-./autogen.sh
+fw_get http://www.impredicative.com/ur/urweb-20140704.tgz
+fw_untar urweb-20140704.tgz
+cd urweb-20140704
 ./configure
 make
 sudo make install