The static buffer is updated:
* reset() is no longer a member. Use b.consume(b.size()) instead.
* Simplified implementaton, uses asio instead of custom types
* Better stream performance: consuming the input makes room
available in the output. This class is now suitable for
HTTP reads.
These changes permit the static_buffer wrapper to adapt a user
memory buffer if desired, including a stack based array.
The static_buffer_n class may also be used for this purpose,
it comes with its own storage.