README: update with setup instructions

Add sections Dependencies, Database setup, and Running.

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
README: /bounds, /around use GET parameters

The documentation was wrong about /bounds and /around requiring a POST
payload.  Fix this.

Spotted-by: Ashok Gautam <ScriptDevil@gmail.com>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
views: return exception error from lookupId, addToken

Catch the exception and return the exception string in lookupId and
addToken, instead of crafting a custom error string.

Signed-off-by: Ashok Gautam <ScriptDevil@gmail.com>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
views: respond with GeoJSON (#3)

GeoJSON[1] is the standard way of representing geo entries.  Return a
GeoJSON Feature from lookupId and FeatureCollection from lookupKey,
lookupToken, lookupBounds, and lookupAround.  The key/ value pairs
from PlaceToken are stuffed into properties.

[1] http://www.geojson.org/geojson-spec.html

Helped-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Ashok Gautam <ScriptDevil@gmail.com>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
CONTRIBUTING: remove the s-o-b requirement

YuviPanda strongly objects against it, saying that it serves no purpose.

Suggested-by: YuviPanda <yuvipanda@gmail.com>