trivial: Add some run time checks for cd_color_rgb_array_interpolate()
libcolord: Fix crash when cd_color_get_blackbody_rgb() with insane values

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=986675
libcolord: Make cd_color_get_blackbody_rgb() return false if temp was invalid

Also add some self tests to make sure this works for all values.
session-helper: Set the status to idle when resuming
session-helper: Do not crash when moving the sensor position

Hopefully fixes: https://bugzilla.redhat.com/show_bug.cgi?id=973792
libcolord: No critical warning if udev_hwdb_new() fails