add some comments about needed refactorisation
prepare refactorisation

- drop unneeded include file
- add new 'cw_utils'
move speedstr definition to cw_utils

- furthermore replace extern definition by including cw_utils.h
refactor CW speed logic

- move 'speed_conversion' to cw_utils
- add SetCWSpeed and use it in parse_logcfg
- add GetCWSpeed and start to use it
drop separate handling of 'speed' and 'keyspeed' variable

- as 'keyspeed' was only used to control display of CW speed we replaced
  it by GetCWSpeed()
refactor

- use GetCWSpeed for rest of functions
add #include guard
bring 'speed_conversion' in sync with 'speedstr'
move calculation of CW message length to cw_utils
cleanup autocq
add a marker in call input field where autosend starts