Enhance OpenCL options UI dialog

1) HIG-ification of blacklist and whitelist, using frames
2) handle Use OpenCL checkbox to enable/disable OpenCL blacklist and whitelist changes

Change-Id: Iae132d09d2dd0436fa1aa2a64e902ee5aed7cf47
Reviewed-on: https://gerrit.libreoffice.org/13602
Reviewed-by: Tor Lillqvist <tml@collabora.com>
Tested-by: Tor Lillqvist <tml@collabora.com>