- Renamed JSEvaluate -> JSEvaluateScript, JSCheckSyntax -> JSCheckScriptSyntax
        - Added exception out parameters to JSValueTo* and JSValueIsEqual because
        they can throw
        - Removed JSObjectGetDescription because it's useless and vague, and 
        JSValueToString/JSValueIsObjectOfClass do a better job, anyway
        - Clarified comments about "IsFunction/Constructor" to indicate that they
        are true of all functions/constructors, not just those created by JSObjectMake*



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@15404 268f45cc-cd09-0410-ab3c-d52691b4dbfc