make %argPresent() return a native bool, and add support for them in generateCondBr.  generates tighter code dealing with parameter+default initialization
make %argPresent() return a native bool, and add support for them in generateCondBr.  generates tighter code dealing with parameter+default initialization

carlosalberto/echo-js,toshok/echojs,toshok/echojs,carlosalberto/echo-js,carlosalberto/echo-js,carlosalberto/echo-js,toshok/echojs,toshok/echojs,toshok/echojs,carlosalberto/echo-js,toshok/echojs,toshok/echojs,carlosalberto/echo-js,toshok/echojs