is_member() requests all members to know if an identity is member will explose

is_member() is currently retrieving the whole list of members from /wot/members to know if an identity is a member or not.

The more members it will be, the more this request will slows down silkaj to determine if an identity is member or not.

The usage of /wot/identity-of/<id/pubkey> says if an identity is member or not when sending error code.

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Todo

• remove not used get_pubkey_from_uid()
• remove get_uid_from_pubkey()
• Replace two uppers function with identity_of() which requests /wot/identity-of/<pubkey/uid> and only returns members identities with their pubkey and uid, which improves performances.
  • In case the identity is not member, try with /wot/lookup/* to know the corresponding uid/pubkey?
• change is_member() as a wrapper of identity_of()
• change usage in id, cert, tx, net, and blocks

If Silkaj requests several time at the same moment, we get a 429 Too Many Requests. #206 (closed) should solves this.

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GVA API should allow one request for all needed identities.