man: clean up the man page.

man: clean up the man page.

Several changes to the man page to tidy it up a bit:
- RCS tag removed
- synopsis shortened, OPTIONS section added instead
- "xinput" dropped before the option descriptions, options in manpage
  prefixed with '--'.
- device_name replaced with just device, since it may be a deviceid.
- Removed references to XI man page calls that some options use, it really
  doesn't matter to users what the underlying Xlib call is.
- mark set-int-prop and set-float-prop as deprecated in the man page.
- add --test_xi2 flag
- Added a few more authors.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Alan Coopersmith <alan.coopersmith@sun.com>