protected RPCMessagesParser

[randaz81]

RPCMessagesParser several calls to various motor control interfaces have been protected so that if an interface is not available in the hardware device (i.e. the view() fails), the controlboardwrapper/yarprobotinterface does not segfaults.

[update-docs[bot]]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would update the release notes by adding a file in doc/release/<target_branch>, based on your changes.