[apparmor] [patches] parser stress fixups and var support

[Seth Arnold]

Thanks Steve, a comment:

+    case rand(50)
+      when 0
+        out = "#{out}/@{#{symtab.get_symbol}}"
+      when 1..4
+        out = "#{out}/#{get_random_regex}"
+      when 2..49
+        out = "#{out}/#{get_random_name(rand(10) + 4)}"

The second and third cases overlap. Because '..' is inclusive, and
'...' is exclusive on the upper element, I suggest:

when 0
  #random symbol
when 1...4
  #random regex
when 4...50
 #random name

The rest looks good :) thanks!