vtd-xml benchmark result can be drastically improved...

[jzhang2004]

1. compile xpath per routing request is slow, take autoPilot.selectXPath out of the evaluation loop and do a global compile at the program start up... that will improve the result by also 80%
2. turn on buffer reuse during parsing will get you another 5%
3. turn on VTD+XML support, this time it will beat the faster one on the graph which is header!!