Changes each adjustment method to take a preserve parameter when
setting the temperature instead of parsing the preserve option
from the command line/configuration file. This helps resolve the
issues around #513:
- This allows the preserve option to be implemented as a
command-line switch (-P). This switch _disables_ the preservation
of existing gamma ramps. Having a command-line switch makes it
easier to use directly with manual or one-shot mode.
- The preserve options is on by default, so continual mode as well
as other modes will default to applying the color adjustment
on top of the current gamma ramps.
- Preserve is always disabled in reset mode so resetting works
as expected again.
Jon Lund Steffensen
e075444663