* Store the random blip positions when generating rd.json
Fixes: https://github.com/AOEpeople/aoe_technology_radar/issues/148
Simple solution to creating stable blips is to store the randomly generated angle and radius in rg.json.
Attempted a few hash functions but found it hard to spread blips 'nicely'
(they tended to clump into groups or sections of the radar).
* distribute points within .1 and .9 of the arc
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Co-authored-by: Bastian Ike <bastian.ike@bare.id>
