* wincap.h (wincaps::is_server): New flag.
(wincapc::version): Change type to OSVERSIONINFOEX.
(wincapc::is_server): New function.
* wincap.cc (wincap_unknown::is_server): New initializer.
(wincap_95): Ditto.
(wincap_95osr2): Ditto.
(wincap_98): Ditto.
(wincap_me): Ditto.
(wincap_nt3): Ditto.
(wincap_nt4): Ditto.
(wincap_nt4sp4): Ditto.
(wincap_2000): Ditto.
(wincap_xp): Ditto.
(wincapc::init): Adapt to OSVERSIONINFOEX. Add detection of NT server systems.
* sched.cc: Include windows.h and registry.h.
(sched_rr_get_interval): Re-implement for NT systems.