Add an environemnt variable
        For Ubuntu, the best place is /etc/environment.  Values placed here do
        not need to be exported.

def add_env(self, key, value):
        """
        Add an environemnt variable
        For Ubuntu, the best place is /etc/environment.  Values placed here do
        not need to be exported.
        """
        boto.log.info('Adding env variable: %s=%s' % (key, value))
        if not os.path.exists("/etc/environment.orig"):
            self.run('cp /etc/environment /etc/environment.orig', notify=False, exit_on_error=False)
        fp = open('/etc/environment', 'a')
        fp.write('\n%s="%s"' % (key, value))
        fp.close()
        os.environ[key] = value