Merge pull request #22 from Mixaill/master

Fix alacarte-importer compilation with MinGW
[renderer] Rename IconCache to ImageCache

It will be used not only for icons but for background images as well
[renderer] Implement pattern fill (fill-image attribute)
[renderer] Implement pattern fill for ways (image attribute)
Merge pull request #20 from alacarte-maps/way-fill

Implement pattern fill for ways and areas (image, fill-image mapcss attributes)
[renderer] Fix build
[TileIdentifier] Use .fallback stylesheet only if the default stylesheet is invalid.
[renderer] Print TileId on every tile (in debug mode)