[fix] make result template map more CSP compliant - simple & oscar

Add osm-map-box in::

    searx/static/themes/__common__/less/result_templates.less

Replaced sty= in files::

    ./oscar/result_templates/map.html:64:        <div style="height:300px; width:100%; margin: 10px 0;" id="osm-map-{{ index }}"></div>
    ./simple/result_templates/map.html:65:    <div id="result-map-{{ index }}" class="invisible"><div id="osm-map-{{ index }}" style="height:300px; width:100%; margin: 10px 0;" ></div></div>

Reported-by: https://github.com/searxng/searxng/issues/57


Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>