[WIP] Support multiple @find-by annotations

Still open tasks but basic support for multiple ```@find-by```. Still requiring some new unit tests and ```ElementCollection``` see #48 for more details.

Closes #13
I just added an non empty array for return to get something returned and merged internally, at the end I do not validate that the final results are merged (cause we only have one annotation) and it could also stay `array()` and we assert against a count of 0.
There was no advantage at the end and it could be reverted to the original assertions.