Hopefully a better choice for defaults will minimise the chance of a bad colour
combination for notetext and notebackground colours when one colour ( more than
likely the notetext colour ) is gleaned from some default ( e.g. like a system
 tooltip colour ). We change the choice from system helptext ( fg & bg ) colours
and use Libreoffice default font and default note background colours instead.
The rationale here being that even in the normal scenario it seems with modern
excel documents the note background colour is a 'real' colour and not an index
( therefore the colour selection from some predefined colour doesn't happen )
But the note text colour is generally a colour index ( therefore a colour is
selected from defaults ). In say gnome3 the default tooltip colour is now white
 and a really bad contrast to the normal background colour for a note. I changed
the code here to use the colours from libreoffice given that the default colours
more or less match Excel default colours ( which will be by far the most
frequently ) used combination

Change-Id: I2ae38a44e0cbf201beb3b7d18a89f5ebdd644f8c