In progress

Describe table  in progress.
Describe, Delete table API implemented
Fixed TableDelete test

Code polishing
Moved responce formatting to action class. PEP8 fixes
Removed mock, mox3 from dependencies. Code polishing
Merge pull request #22 from zaletniy/api

Implemented TableDelete, TableDescribe API
Storage interface fixed

Now it supports projections and ordering in select_item request