Add a soynode accessor to the Matador API, which is important to expose b/c of how soynode uses global state

Hello @dpup, 

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

e6cb5a4c97926dc0d1596c6a2a14f7a3032f133c (2013-11-05 12:14:27 -0500)
Add a soynode accessor to the Matador API, which is important to expose b/c of how soynode uses global state

Check list:


R=@dpup