fix running go with absolute paths.
don't create runners manually.
fix restart on file change when autorestart is disabled.

you had to save the file twice to make it restart then. (because the
first time the runner goroutine would quit and then the second time
restart would actually restart the goroutine and then it would work.)
try to clarify autorestart vs restarting.

autorestart restarts when the command exits, otherwise restarts only
happen when the file is saved.