[FA]{issue} I56 - more tiles

#56
Small tile improvements.
[FA]{issue} I56 - more tiles

Closes #56
-Improved existing tiles
-added sewer tiles (straight, corner, straight with bridge)
-added 2floor variants with cracks
Merge remote-tracking branch 'origin/vadler_dev' into fadler_dev
[FA]{issue} I65 - Slider Size

Closes #65
-Increased slider size image to 40x40
-Added texture packer project
-some minor asset wip gui folder reorganization
Merge remote-tracking branch 'origin/fadler_dev' into vadler_dev