Added random2 (InvGamma prior) option for random Strata-Year interactions (previously random2 was only available for vessel and vessel-year interactions) 

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/nwfscassmt@200 edb9625f-4e0d-4859-8d74-9fd3b1da38cb