First pass at using "formats" rather than a single writer class. Added a bit of flexibility in the postgis source. Added MVT format.
Actually deal with options in formats. Add :mercator option for :coordinates. Add :clip option.
Remove server command and viewer app
Rename Index to Tile
Drop MVT support
Make :tile coordinates the only supported coordinates for the JSON source
Complete list of PostGIS query options
Remove non-configurable :coordinates attribute
Add GeoJSON format
Make GeoJSON the default format
Fix GeoJSON output
Add basic server and tourism example
Move server to examples, main example is the victoria tourism map
update examples
Use parse_file for server example
Move --compress handling to render command
Remove callback and metatile options
Make the path option support %% -> %
Tile.parse should be a class method
update readme