Provide error handling for Reboot() call

[invidian]

Right now user has no way of knowing if calling Reboot() succeeds or not, as no error is returned from a call. E.g. if user calling it has no permissions to do so, the call will silently fail.

This could be improved, e.g. together with accepting the context for operation in new function.

[lucab]

Good idea, a RebootWithContext would fit nicely. Would you like to submit a PR with that?

[invidian]

Can't promise I find time to do so, but will try :)

[invidian]

Ah, just found out there is more general issue for this: #326, not sure if it make sense to address each method individually or should we handle all of them at once.

[invidian]

Created #390 to address this.