replaced C level random number generator rand() with R random number handing and the unif_rand function

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/partykit@614 255f4249-2263-4417-b1ea-8498779e27a7
updated some example output

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/partykit@615 255f4249-2263-4417-b1ea-8498779e27a7