Heavy work on while tag. Still needs work.

tests/testfor.jet

@@ -1,6 +1,6 @@
-#!./jet-2.0
+#!../jet-2.0
 <jet cgi="true" name1="localname" filterblanklines="true" trimlines="true">
- <for name="ix" start="1" end="5" step="1">
+ <for name="ix" start="1" end="5" step=".1">
   -->#[ix]<--
  </for>
 </jet>