Turns Response into a QObject and sets parent to the
command that emits it.
Each Command is also a child of the decorator commands,
Timeout and PageLoading commnds, so that deleting the
top level command will delete all the children.
See discussion in #430.
Timeouts can be set using browser.timeout = <seconds>.
When a command or page load takes longer the specified
timeout a Capybara::TimeoutError will be raised. Calls
to reset! will reset the timeout. You can also clear
the timeout by setting it to -1.
The timeout is implemented as a Command decorator.
Matthew Horan