#1431 Check for directory existence even if HOME is defined

git-svn-id: https://svn.qindel.com/repos/main/projects/qindel/QVD/src/trunk@21870 4046b530-fbad-4e16-af16-ee11f0b55167
#1431 Check first for cert dir and then set NX_HOME

git-svn-id: https://svn.qindel.com/repos/main/projects/qindel/QVD/src/trunk@21871 4046b530-fbad-4e16-af16-ee11f0b55167