wmllint double-quotes IDs containing single-quote.

This diff also fixes two comments where the lift code was 
a bit overzealous.  No real harm done, fortunately.

data/campaigns/Under_the_Burning_Suns/scenarios/06a_In_the_Tunnels_of_Trolls.cfg

@@ -418,7 +418,7 @@
             value=0
         [/set_variable]
 
-        # create AI="guardian units. They can't move unless an enemy"
+        # create AI=guardian units. They can't move unless an enemy
         # moves nearby. I create them at the beginning because when the
         # player sees them, events will fire.
 

data/core/units/monsters/Skeletal_Dragon.cfg

@@ -2,7 +2,7 @@
 [unit_type]
     id=Skeletal Dragon
     name= _ "Skeletal Dragon"
-    #not 'race="monster', because we need the not_living attribute"
+    #not 'race=monster', because we need the not_living attribute
     race=undead
     image="units/monsters/skeletal-dragon.png"
     hitpoints=86

data/tools/wmllint

@@ -856,9 +856,11 @@ def hack_syntax(filename, lines):
             try:
                 (key, prefix, value, comment) = parse_attribute(lines[i])
                 if "'" in value and value[0].isalpha() and value[-1].isalpha():
-                    lines[i] = prefix + '"' + value + '"' + comment + "\n"
-                    if verbose:
-                        print '"%s", line %d: quote-enclosing attribute value.'%(filename, i+1)
+                    newtext = prefix + '"' + value + '"' + comment + "\n"
+                    if lines[i] != newtext:
+                        lines[i] = newtext
+                        if verbose:
+                            print '"%s", line %d: quote-enclosing attribute value.'%(filename, i+1)
             except TypeError:
                 pass
     # More syntax transformations would go here.