* Client terminal initialization data is now received
asynchronously. To facilitate this, a couple of minor changes to the
protocol was made:
- The client now starts with sending a 4-byte unsigned integer
with the *total* size of the initialization data (*not*
including the size field itself.
- Strings (TERM variable + argv) are now sent NULL-terminated
* The server allocates a single buffer, and fills it
asynchronously. When full (as indicated by the initial 'total size'
integer), we parse it (taking care not to read outside boundaries
etc, and verifies the lengths (of the TERM variable and argv array)
indicated by the client matches the actual lengths of the strings
received.
* The server now ignores 'unexpected' data received from the client,
after the terminal has been instantiated.
