new tool: symnamer

[kohlhase]

Currently \symdefs often do not have a good symbol name, and then -- e.g. in the learner model overview -- the macroname becomes visible to the students.

Therefore I would like to go over the corpus and supply good names. I suspect that it would be relatively easy to build a new tool symnamer that steps through all \symdef occurrences and allows me to supply better symbol names.

Concretely, if symnamer finds a \symdef{foo}[<keys>]{...}, where

• <keys> do not have a name= attribute or
• and there is no comment symamer: foo coment at the end of the file
  then symnamer asks the user for a symbol name. If the user answers
  *bar, then it changes the \symdef to \symdef{foo}[name=bar,<keys>]{...} (possibly adding the square brackets
• the empty string then the entry is skipped
• Control-D (or something easy that is not misinterpreted as a name) then a comment symnamer: foo is added at the end of the file.
  I think that is all we need.