Antispam + quota mechanism

Since any key can submit data to the network, the datapods need an antispam mechanism.

It is important to accept data from users which are unknown to the blockchain since it is a way to appear on the map. These users can be added in a limited number (e.g. rate) and with a low quota (number of documents and bytes stored).

Then, when a profile receives a trust sign from the known network (star for example) its quota can be increased to match the one from a normal user.