[STORE] Added `MyModel.all` finder method

    Person.all.to_a

    # 2014-05-05 15:02:24 +0200: GET http://localhost:9250/people/person/_search [status:200, request:0.047s, query:0.024s]
    # 2014-05-05 15:02:24 +0200: > {"query":{"match_all":{}},"size":10000}
    # 2014-05-05 15:02:24 +0200: < # {"took":24,"timed_out":false,"_shards":{"total":5,"successful":5,"failed":0},"hits":{"total":100,"max_score":1.0,"hits":[ .... ]}}
    # => [#<Person:0x007ff1d8fb04b0 ... ]