Add `singleton_mgr::force_initialization()`
This function force a initialization of the requested module. If the module is already
initialized, this function has no effect. This is recommended for modules which
has its own thread running (e.g. `SERIAL_PLUGIN`).
Add check for correct defines in `config.h`
Streamline FSM for Conveyor 2
This introduce new functions in `token_mgr`. For example `token_mgr::check_order(bool)`
which check if the current token is the expected token. Also new is `token_mgr::request_motor_left()`
and `token_mgr::unrequest_motor_left()`. All request and unrequest functions in `token_mgr` now
comes with an optional argument `update` (Default: True) which allows to skip the `update()` call.
`token` comes with a new function `set_vals_from_telegram(const telegram&)`.