Only raise WriteError if error callback is not defined. See updated documentation for details
Forgot a :
Typos in documentation
status now responds with version and cookie by default
Add a catch WriteError when processing command, then could have caused a crash
address tweaks
Make shackhartman_command_handler use errorcallback as an example of clean code at the expense of error messages and document SLITS_command_handler as a counterexample
Add general support for commands which result in empty replys.

By default semdmessage sends nothing if an empty sting is sent, so send
'/n' explicitly if the command reply is an empty string.
FLSIM_INSERT and FLSIM_REMOVE are not commands
FILTER IN and FILTER OUT are not commands and thus do not need to be checked for
max_clients is already set to 1 by agent
Rearrange __init__ for readability
Add the guider agent connection
""" Does not work as a block comment
Use a global parameter for the version string
Create (and document) a basic implementaiton of the plugmode command handler to test the fls inserters
Remove pointless conde from plugging command handler and document
Formatting
Add the command handler for the guider system
Remove ununsed legacy code