The behavior of QWebFrame::toPlainText is undefined if the content
contains non-Latin1 characters. In Qt 5, additional MIME types are
considered supported, so there's no way to get at the raw data when
unsupported content has been loaded. Instead, proxy network replies
through NetworkReplyProxy which provides repetitive reads.
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.
Matthew Horan