Use the threading module instead of thread

The thread module is not present in python3, hence it is not portable
between python2 and python3.
Changes to the native host install script

The nutty.py script is installed into /opt/nutty on Linux systems.The
manifest file has been modified to reflect the change in the script
path.  The install script also checks if it being run as root on Linux.
Merge pull request #5 from kshlm/script-fixes

Changes to the install_script and the native host script