Allows expansion of array of values in query

Permits: db.query("SELECT * FROM t WHERE f IN (?)", [ [10,20,30] ])
Update Client.js
Cleaned up value formatting

Streamlined prepare() and moved value formatting code to _format_value()
Added metadata option to return column type and charsets
Merge pull request #34 from japhy-/patch-1

Handle arrays when doing substitution for prepared queries
Merge pull request #37 from roamm/master

Minor Improvements
Merge pull request #40 from sequelize/master

Added metadata option to return column type and charsets
Fixed a memory leak for when we're destroying the client.

We kept around event emitters that kept a reference to the client. We now call removeAllListeners on 'close'
Merge pull request #45 from arianitu/fix_destroy_memory_leak

Fixed a memory leak for when we're destroying the client.
Unref() object when connection is closed
Merge pull request #47 from Nibbler999/unref

Unref() object when connection is closed