init with architectural sketch
Completed Isi::FreeChat::PostOffice::Address
Completed Isi::FreeChat::BuddyBook::BuddyEntry
Added isi/lib.rb which adds functionality to standard ruby in some ways
Changed db_hello and db_bye to take module names to show besides  hello/bye
Rearranged modules, added ModuleRootDir in all of them and added chained requires for everything.
Added some minor normalization for ip addresses in PostOffice::Address
Changed isi/lib db_hello and db_bye : $isi has to be there
Completed PostOffice::send_to / added Unit test for PostOffice
Completed BuddyBook::BuddyBook
Added PostOffice#reachable?
Added thread to periodically clean idle connections / synchronized access to connections around that / added public method PostOffice#close_down which cleans up connections and stuff / In the middle of implementing the server thread
Included Integer#bytes and Integer.from_bytes in isi/lib / Added a test for the lib
Added Integer#to_bs and Integer#to_hs in isi/lib
Added server threads in PostOffice / Changed socket creation method (Socket instead of TCPServer) / Suspending connection cleaner functionality for now
Added script for irb testing of PO
Added logger in PO
Added specific loggers in PO
PO can receive message header: message length
Added generic exception handling in receiver lambda (because they are not reported otherwise...