Hpux support

Hi,
comments included in commit messages, hpux.c has been modified from sunos.c source. 
We would like to use Avatar-js in our projects on all platforms including hpux and libuv is requiered by Avatar. To test libuv in real scenario we have to wait for Java 8 availability on hpux which is prereq for Avatar.
Regards
Jachym
Czech Republic