IIIF 1.0 now uses pixel based syntax

Storing tiles for IIIF tests using percent based sizes (e.g. `/0,0,512,512/pct:50/0/native.jpg`) were breaking the repo for Windows devs. 

IIIF 1.0 now uses pixel based size requests, only specifying one dimension (the width, e.g. `/0,0,512,512/256,/0/native.jpg`) so that only IIIF level 1 compliance is necessary to use OpenSeadragon. Percent-based sizes are also a level 1 feature, so any server that supports this should also support `w,` sizes (`w,h`) is a level 2 feature.

The test tiles have been updated to reflect this change.