Clarified Readme for spider option
Clarified Readme for spider option

Clarified what is required to use the spidering in the readme file.

frob/wraith-selenium,jzinkdi/wraith,adouglas/wraith,LessonPlanet/wraith,BBC-News/wraith,guimoreira07/wraith,webdev1001/wraith,BBC-News/wraith,jlarusso-canvas/wraith-time-diff,adouglas/wraith,frob/wraith-selenium,LessonPlanet/wraith,LessonPlanet/wraith,peruukki/wraith,webdev1001/wraith,webdev1001/wraith,jzinkdi/wraith,OfflineAudio/wraith,guimoreira07/wraith,jzinkdi/wraith,BBC-News/wraith,marciovicente/wraith,marciovicente/wraith,saulirajala/wraith,deividmarques/wraith,jaredstehler/wraith,jlarusso-canvas/wraith-time-diff,sideci-sample/sideci-sample-wraith,marciovicente/wraith,frob/wraith-selenium,jaredstehler/wraith,peruukki/wraith,sideci-sample/sideci-sample-wraith,guimoreira07/wraith,saulirajala/wraith,deividmarques/wraith,adouglas/wraith,OfflineAudio/wraith,deividmarques/wraith,jaredstehler/wraith,saulirajala/wraith,peruukki/wraith