Add support of searching a game for a group of players

[Relrin]

For now the matchmaking microservice is supporting only searching a game for a solo players and doesnt provide any opportunity to find a game for a group of players, when they are playing together. For making this feature as available we will need:

• Update documentation for strategist and matchmaking microservices.
• Middleware layer on the post-processing stage must extract the data from external storage for each player in the group and put in the request body
• Search workers must take into account the case when coming a request with a group of players and send the an appropriate request to strategist microservice for further processing
• The strategist microservice, probably, must be updated so that can accept the data with the group of players and seed them together in one team