Cherry-Pick 03ba6507: Return a date as a string if it fails to parse.

Conflicts:
	src/odbc.cpp
Always use SQLExecDirect in UV_Query (works just as well as SQLPrepare, with less overhead)
http://msdn.microsoft.com/en-us/library/ms811006.aspx#code-snippet-35
Further SQLExecDirect work (missed QuerySync out), and updated benchmarks. Fixed a couple of cases where many queries were being run concurrently, causing errors.
Pass through the STDERR stream of the child process when running benchmarks
Merge branch 'query-using-sqlexecdirect' of https://github.com/lee-houghton/node-odbc into v0.6