bugfix: FIA calculation (especially added mConst correctly).

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/mptinr@129 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Removed the RcppEigen bug and appeasing CRAN.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/mptinr@130 edb9625f-4e0d-4859-8d74-9fd3b1da38cb