move code out of the factory into the OpenGL implementation

one step closer to a stateless factory

Change-Id: If491a53d9ce0d27244d4df293de7792019539c33
move Circle to OpenGl backend and out of the factory

This finally makes the factory stateless again. Now it is possible again
to render more than one chart in the OpenGL backend.

Change-Id: I9d1a24dabb2bdf5aacd05cbe2931924f27aafeca
add some code to list the properties for debugging

Change-Id: I0ebad4112899965dea0da9da44c5f4b7b444948e
remove leftover pieces to amke factory clearly stateless again

Change-Id: I0744ebed41cc1c9bbf40ef2caecb8d97baf177e6
remove unused method

Change-Id: I0ed8082ceb42f2b1c89571884b46bf537507abb2
remove one more unused method

Change-Id: I6801486c09e5fdfe9a7a00c42503c3701f77cd54
use initializer list in constructo

Change-Id: I772f6cf195e48b4efba86e50efeaef32d5b9639b
some inital work on merging all the rendered shapes

Change-Id: Ic8e68e1311393d5f2115412a703e3d86b91e1df8
activate the new rendering code

Change-Id: Ie5b8ef035610d5ca26b418ec966d3eaa95966241
add more debug output

Change-Id: I41710783f1f2d448110b5db8e9c2e7955e2ed5a7
add color to bubbles

Change-Id: Id851916a160b65360ee0dd4bbe67b5246067b659
add more debug output

Change-Id: Ib9454f6fec6988899161e59c066fcc384e286200
one more change to the rendering

Change-Id: I36ba16e8ccb8782c9fd85d7cf772d74ffab5a7f7