using track changes in latex using changes package

Example from the link

http://tex.stackexchange.com/questions/65453/track-changes-in-latex

documentclass{article}

\usepackage{changes}
\usepackage{lipsum}% <- For dummy text
\definechangesauthor[name={Per cusse}, color=orange]{per}
\setremarkmarkup{(#2)}


\begin{document}
\lipsum[1-7]

This is \added[id=per,remark={we need this}]{new} text.
This is \added[id=per,remark={has to be in it}]{new} text.
This is \deleted[id=per,remark=obsolete]{unnecessary}text.
This is \replaced[id=per]{nice}{bad} text.

This is \added[remark={we need this}]{new} text.
This is \added[remark={has to be in it}]{new} text.
This is \deleted[remark=obsolete]{unnecessary}text.
This is \replaced{nice}{bad} text.


\listofchanges
\end{document}

And the nice thing is that if you supply the final option to the package declaration that is \usepackage[final]{changes} it clears the traces of changes made by the authors and respecting the last changes.