Sync unit-test documentation syntax exemplar with description and behavior.

--- basis/tools/test/test-docs.factor	2010-07-12 12:28:48.000000000 -0400
+++ basis/tools/test/test-docs.factor.orig	2010-04-15 23:56:46.000000000 -0400
@@ -53,7 +53,7 @@
 ABOUT: "tools.test"
 
 HELP: unit-test
-{ $syntax "{ output } [ input ] unit-test" }
+{ $syntax "[ output ] [ input ] unit-test" }
 { $values { "output" "a sequence of expected stack elements" } { "input" "a quotation run with an empty stack" } }
 { $description "Runs a quotation with an empty stack, comparing the resulting stack with " { $snippet "output" } ". Elements are compared using " { $link = } ". Throws an error if the expected stack does not match the resulting stack." } ;