Project consists of three components: server, stream, and storage. Each need not
know the implementation details of the others. Stream and Storage are
presented as base classes with Fifo and Phobos_file serving as
implementations. Inter-component communication is reworked such that the
stream acts as an exclusive interface between the server and storage.

Change Log:
* Rename backend to storage
* Rename fifo to stream
* PUT logic functions like server->stream->storage
* GET logic functions like storage->stream->server
* Each stage represented by a class
* Communication between stages handled by class ownership
* Ownership is server<stream<storage
* Server does not communicate with storage and visa/versa
* Each stage Know nothing of the implementation details of the others
* Stages see each other ass abstract interfaces
* Request handlers must be initialised with unique pointer to a Stream derived class as a constructor argument.
* Streams must be initialised with unique pointer to a Storage derived class as a constructor argument.
* Phobos_file closes file immediatley after finish IO to prevent Stream
from blocking in the case of FIFO Stream implementation
* Remove DEBUG print statements
* Rename server.cc to server.main.cc to reflect presense or main
function