Fixed issue with too many closing parenthesis.

For this a macro is introduced, which replaces the boiler plate of the
emmitting of parenthesis.
The macro will not emmit closing </span> tags, for non-matched closing parenthesis.

This is not the most beautiful way of fixing this, however it replaces quite a bit of boiler plate code and fixes the issue in the boiler plate.

Note that I added alexandria as a dependency, this is not really needed, I use it for only-once.  

I can easily remove the dependency on alexandria.

Also, if you do not like the macro approach, I can apply the same fix in all the places the paren-counter is decremented.

Kind regards, 
Wim Oudshoorn.