:space_invader: refactored tilestache code
:space_invader: refactored tilestache code

nypl-spacetime/nypl-warper,nypl-spacetime/nypl-warper,NYPL/nypl-warper,NYPL/nypl-warper,NYPL/nypl-warper,nypl-spacetime/nypl-warper,NYPL/nypl-warper,nypl-spacetime/nypl-warper