Add get/setPart to ITiledRenderable, and implement for sw/sc.

Change-Id: Iec3d6374f029149cadf8fb9c9b16fec90146c31e
LOK DocView: implement part selection.

Change-Id: I2e16ca9d2d5fcd25b0435f1b9b0fbcb52b92e012
Add part selector to gtktiledviewer.

Change-Id: I569c8f0ebf4476c0a247cde15a263d1db956a14b
Add Tiled Rendering outline to sd.

Change-Id: I810d827f330690f8071b662b9ddd05cc41655a71
svp clipping again: Rectangle dimensions don't map directly to B2IBox.

This is the same as in 80f3211a7aeff221718703c445be4c753e0a1067.

Change-Id: Ibb981da064b4fc97fd865be2decabd8798de7380
Introduce osl_areCommandArgsSet.

We cannot call osl_setCommandArgs twice, however there is currently
no way to determine whether or not this has already been done. This is
necessary e.g. for LibreOfficeKit where we may also be using UNO
separately (and also for unit tests where LO is already set-up prior
to the unit test running, and therefore we can't set up osl again
from within LOK).

Change-Id: Id1f357ef604eb2b6b7814c9a04ac6933a39fd3eb
Check whether Command Args are already set up before doing so.

Could already be set up e.g. if a client application is using UNO
separately, in addition to LOK.

Change-Id: I50c3230b6f2456360273902a308c303576baac10