Removed the numerical integration routine - there is a closed form after all

git-svn-id: http://beast-mcmc.googlecode.com/svn@6568 ca793f91-a31e-0410-b540-2769d408b6a1
Added support for multi-parameter kernels, and a specific logistic implementation

git-svn-id: http://beast-mcmc.googlecode.com/svn@6569 ca793f91-a31e-0410-b540-2769d408b6a1