fix rounding bug with unconventional tile sizes, close #2288
fix rounding bug with unconventional tile sizes, close #2288

iZucken/Leaflet,jasonoverland/Leaflet,akrzyzanowskino/TeamSE,frogcat/Leaflet,codeator/Leaflet,CapeSepias/Leaflet,Neorth/Leaflet,rlugojr/Leaflet,stefanocudini/Leaflet,Trufi/Leaflet,iZucken/Leaflet,iZucken/Leaflet,codeator/Leaflet,scaddenp/Leaflet,brah/Leaflet,CapeSepias/Leaflet,codeator/Leaflet,msiadak/Leaflet,sisou/Leaflet,tsantacruz/RotationalMarker,rlugojr/Leaflet,geoloep/Leaflet,sisou/Leaflet,davojta/Leaflet,AP-whitehat/Leaflet,msiadak/Leaflet,frogcat/Leaflet,brah/Leaflet,Leaflet/Leaflet,akrzyzanowskino/TeamSE,Trufi/Leaflet,scaddenp/Leaflet,brah/Leaflet,Trufi/Leaflet,Ubisense/Leaflet,stefanocudini/Leaflet,geoloep/Leaflet,jasonoverland/Leaflet,Leaflet/Leaflet,geoloep/Leaflet,iOffice/Leaflet,iOffice/Leaflet,Ubisense/Leaflet,msiadak/Leaflet,Ubisense/Leaflet,CapeSepias/Leaflet,davojta/Leaflet,akrzyzanowskino/TeamSE,AP-whitehat/Leaflet,AP-whitehat/Leaflet,tsantacruz/RotationalMarker,davojta/Leaflet,Neorth/Leaflet,stefanocudini/Leaflet,Leaflet/Leaflet,frogcat/Leaflet,Neorth/Leaflet,tsantacruz/RotationalMarker,iOffice/Leaflet,rlugojr/Leaflet,sisou/Leaflet,scaddenp/Leaflet,jasonoverland/Leaflet