[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
Looks correct, but I wonder what will happen if that is `@var WebElementCollection` in the `TypifiedPage` class descendant and this decorator will process it. Yes, it will detect a collection, but attempt to add any found `WebElements` in it will probably fail with exception. Need to have test to ensure that all works without exception here.