Refactor the tagging mechanism

[dbosk]

Refactor the tagging mechanism

[dbosk]

This is especially necessary if a question covers several intended learning outcomes (ILO), the tag for an ILO might be a long name.

[dbosk]

This type of tagging makes #7 difficult. One solution is to replace all tags, another is to keep track of the differences and then edit. The first approach can ruin the structure of the question and tags, e.g. I add tags in relation to the text in the question:

\question Describe the following
\begin{parts}
% tags: crypto
\part cryptography,
% tags: privacy
\part privacy in decentralized systems
\end{parts}

So the second approach seems better. Probably we should add an option (-m ?) for whether the interaction should modify the tagging.