Remove function wrapping and all |global| refrences from helpers.js
Remove function wrapping and all |global| refrences from helpers.js

Originally I wanted to be very explicit with accesses to global object,
but since all this file is about extending it, the |global.| qualifier
seems more like noise.

wwall/pegjs-fn,GerHobbelt/pegjs,Mingun/pegjs,luisvt/pegjs,wwall/pegjs-fn,pegjs/pegjs,jlturner/pegjs,Sciumo/pegjs,jlturner/pegjs,luisvt/pegjs,Sciumo/pegjs,Mingun/pegjs,mcanthony/pegjs,crguezl/pegjs,mcanthony/pegjs,crguezl/pegjs,pegjs/pegjs,GerHobbelt/pegjs