multi-row result-set performance improvement

Multi rows resultset parsing object is ported by column object, resulting in bad javascript compilation, functions beeing created for each resultset.
Benchmarks show that results are the only one less performant than mysql2 driver (ok for mysql driver).
mysql2 does some impacting choice with client side metadata caching + precompilation, which are not options put on the table

improvement :

• avoiding buffer copy when receiving socket buffer when not in multi-part
• metadata parsing improvement
• removing parsing function from column, setting them in dedicated function, permitting javascript compilation improvement