Sea caves tileset

The Sea Caves tileset contains the following themes:

= Features: =
 * Big Door 1
 * Big Door 2
 * Bridge Door
 * Cave Pool w/ Barrier
 * Chessboard
 * Door Transition
 * Exit 1
 * Exit 2
 * Exit 3
 * Hot Springs
 * Pillar 1
 * Pillar 2
 * Portal
 * Stairs Down 1
 * Stairs Up 1
 * Tile Floor
 * Treasure 1
 * Treasure 2

= Groups: =
 * Fountain Large
 * Platform 2 2x2
 * Platform 3 2x2
 * Platform 4 1x2
 * Platform 5 1x2
 * Sea Idol
 * Stairs Down 2x2
 * Stairs Up 2x2
 * Wall Section 1 1x2

= Terrain: =
 * Bridge
 * Corridor
 * Doorway
 * Eraser
 * Floor
 * Wall
 * Water