Stats rest implementation

[ridicoulous]

11 implementation. Added stats dto's, urls and tests

[semashkinvg]

@ridicoulous in addition to my comment. you can sort out what settings should be changed in the account and if the test becomes green, then leave the test and add a comment about should be changed within the account. Otherwise, let's just get rid of this test

Thanks,

[ridicoulous]

@semashkinvg take a look at QueryStringParams.cs. I included datetime fromatting, which those query is valid for server. Is it a good idea?

[semashkinvg]

@ridicoulous will do

[ridicoulous]

@semashkinvg What went wrong with orders testing? I'm adding comments from bitmex docs to classes and fields now. And what will do?

[ridicoulous]

Chat, Settelment, Schema will be later