Step1: Basic concept, move stuff to svx and new
SdrFrameBorderPrimitive2D

Step2: Adapt all creators/usages to use
SdrFrameBorderData/SdrFrameBorderPrimitive2D,
check functionality

Step3: Re-implement mergre of BorderLinePrimitive2D
during decomposition of SdrFrameBorderPrimitive2D
to keep the number of primitives low from the start,
make merge optional (not urgently needed)

Step4: Migrate and isolate all helper methods
and classes involved in geometry creation of border
lines to the implementation (.cxx) of the new
primitive

Change-Id: I840b6765439bd995f2c57ef36315427b1f0f3e21
Reviewed-on: https://gerrit.libreoffice.org/62247
Tested-by: Jenkins
Reviewed-by: Armin Le Grand <Armin.Le.Grand@cib.de>