Enhance the SELinux postinstall script

Currently the SELinux postinstall script just updates the FC file locations:

$ cat .postinstall-selinux 
#!/bin/sh
#
umask 077

currentDir=`pwd`

# Fix selinux file context locations
sed -i -e "s:@@CWD@@:$currentDir:" selinux/jws5-tomcat*.fc

After users run that, they need to build the policy and apply it with semodule manually. We should be able to do that in the script too.