[partner_gogocartojs] Add element.json controllers to return dataset of geo point

[njeudy]

Controllers

Add controler that search res.partner and create json file with this Doc and this One.

This controllers is in public mode.

Model

Add a boolean fields "publish_in_gogocartojs" that is computed by a fonction to give opportunity to other module to add own rules Select only partner that have this field checked to send to gogocartojs.

[njeudy]

not needed anymore with new gogocarto module