Testing SSI/shtml variables

1. Test 1: Idea from http://stackoverflow.com/questions/4076856/ssi-set-variable-and-echo-issue

   Set with < --#set var="taskvar" value="1"-->
   Echo with < --#echo var="taskvar"-->
   

   Increment a variable: Can't be done in SSI.

   See http://stackoverflow.com/questions/29651728/is-it-possible-to-increment-an-ssi-variable-by-1 because variables are just strings.

   You can do it with CGI somehow: see http://docstore.mik.ua/orelly/linux/cgi/ch06_02.htm, but it looks tricky.