Tons of Changes.. Read Description

Client & Server::
Added 2 new functions: (in client and server)
- printing errors
- transfering Cprotocol packet to a buff ready to be sent

Modified some comments and the command text in client

fixed some errors when sending (pck_buff instead of packet)

modified Quit operation to handle ACK packet, not completed

Added Seq and NextSeq variables.

Added Put functionality, not completed.

Cprotocol::
Modified to_protocol() to handle data (should work)

Modified cprotocol_toString() , now cleaner code

ListFiles::
Completely overhauled retrieve_files_name (which originally only retrieved a single file name in the list at a time) to new function list_files() that takes the directory path and returns all the filename in the directory. (It returns each file name separated by '\n' has a string)