Update mocks to use with new podium interface (topfreegames#30)

Add query params to lib method GetMembersAroundMember (topfreegames#28)

improved expiration results printing

Allow using worker as a lib from another service.

removed echo dependency

Feature/grpc (topfreegames#23)

* healthcheck working with http and grpc

* HealthCheck, Status, RemoveLeaderboard and TotalMembers implemented

* BulkUpsert implemented

* UpsertScore implemented

* IncrementScore implemented

* GetMember implemented

* GetMembers implemented

* RemoveMember & RemoveMembers implemnted

* added grpc tests for GetMembers, RemoveMember & RemoveMembers

* GetRank implemented

* GetAroundMember implemented

* GetTopMembers implemented

* GetTopPercentage implemented

* UpsertScoreAllLeaderboards implemented

* refactored UpsertScoreAllLeaderboards

* GetRankMultiLeaderboards implemented

* GetAroundScore implemented

* fixed tests

* added middleware to remove trailing slashes

* added logger middleware

* bumped go version

* bumping even further go version

* updated golang.org/x/sys dependency

* changed test server creation to let listen select random port

* converted remaining middlewares

* added auth

* echo is not more

* prepared score TTL for receiving default 0 values

* refactored app & fixed a goroutine leak

* added a few comments & refactored a few methods

* fixed tests

* changed podium.proto based on uber prototool linter recommendations

* refactored & added test for basic auth middleware

* refactored based on comments

* removed easyjson

* refactored .proto

* another refactor based on comments

* final refactor based on comments

* bumped version

* fixed build, fixed gracefull shutdown, exposed grpc port

Documentation for lib (topfreegames#22)

* added documentation for podium's library

* recovered Testing section of README

* added godoc reference + documentation improvements

Include leaderboard id in logs.

update on lib mock

configurable max connections on lib