Added section on develop install for smif and gui
Added section on develop install for smif and gui

tomalrussell/smif,nismod/smif,willu47/smif,willu47/smif,nismod/smif,tomalrussell/smif,nismod/smif,willu47/smif,willu47/smif,tomalrussell/smif,tomalrussell/smif,nismod/smif