Optimize node compilation a bit. Improves medium startup time by a few seconds

Hello @eford1, 

Please review the following commits I made in branch 'nick-compile-speed'.

02dfa545be1838319b57e29c1e3eed781e50f0bf (2013-08-19 15:36:40 -0400)
Optimize node compilation a bit. Improves medium startup time by a few seconds


R=@eford1