Add comment regarding 'exit' as keyword

preamble.tex

@@ -205,7 +205,9 @@
     morekeywords=[1]{}, % blue Keywords
     morekeywords=[2]{% blue + bold keywords
         annotation,assert,block,break,class,connector,constant,constrainedby,discrete,%
-        each,encapsulated,enumeration,else,elseif,elsewhen,end,exit,expandable,extends,external,final,flow,for,%
+        each,encapsulated,enumeration,else,elseif,elsewhen,end,%
+        exit,% henrikt-ma: What is 'exit' doing here?
+        expandable,extends,external,final,flow,for,%
         function,if,in,inner,initial,input,import,loop,model,nondiscrete,operator,outer,%
         output,package,parameter,partial,record,redeclare,replaceable,return,%
         size,stream,terminate,then,type,when,while,within,algorithm,equation,%