Added links to the project's Twitter and Tumblr accounts.
Defined the json_writer class.
Implemented the json_writer#write_null() and #write_bool() methods.
Implemented the json_writer#flush() method.
Implemented the json_writer#begin_object() and #finish_object() methods.
Implemented the json_writer#begin_array() and #finish_array() methods.
Renamed json_writer#write_bool() to #write_boolean() per RFC 4627.
Implemented the json_writer#write_number() method.
Implemented the json_writer#write_string() method.
Defined the json_writer#write(json_value) overloads.
Ensured that json_writer#write_number() rejects Infinity and NaN.
Began implementing state change machinery for json_writer.
Implemented the json_writer#write_integer() method.
Implemented the basic state machine for json_writer.