Refactored: removed unnecessary code
Refactored: after understanding how elastica works
Added adaptor to separate internal api from Elastica api. This was necessary since Elastica has several errors in handling documents and their data.
Raised accessibility level to "abstract" to prevent PHPUnit to recognize the test case as test suite.
Added more features like adding a Document, unfortunately updatinf a doc does not work yet
Added a custom exception to be able to identify exception thrown by the adaptor