For collaboration it is nice to have environments for comments from particular persons. Here we define the environments rhx for Ralf Hemmecke and mrx for Martin Rubey.
In addition to the ToDo environment we introduce a BUG environment. It should be used for bugs of any kind, no matter whether they are compiler bugs that need workarounds or bugs in Combinat that someone spotted but nobody had time to fix it.
For simplicity reasons we introduce a BUG! environment (which should not be used directly) and wrap it with a ToDo environment with the understanding that every bug has to be resolved at some point in the future and thus is a ToDo.
In particular, it inside that environment, the person that detects the bug should be prominent as well as the date when the bug was detected.
We probably need to introduce an optional parameter that states the seriousness of the bug.