Add option to relabel with current numbering

[tdegeus]

In the case that labels are simply the float number, the formatting can ensure that the right number is used. For example

\begin{equation}
\label{eq:4}
...
\end{equation}
...
\begin{equation}
\label{eq:2}
...
\end{equation}
See \cref{eq:4}

should be changed to

\begin{equation}
\label{eq:1}
...
\end{equation}
...
\begin{equation}
\label{eq:2}
...
\end{equation}
See \cref{eq:1}