[BUGFIX] Use correct options

Instead of using the options_heap in the loop that triggers
oc_render_start_drawing() the options_to_process variable
is used because this is the one that is processed in the
loop.

With the old version it was possible that the wrong options
are used when rendering multiple orgcharts.
[FEATURE] Make JSON data load optional

The data can now be set directly using the new pushToDataArray()
method. This makes the JSON requrest that fetch the data from
an URL optional.