fixed #207 (stricter comparison of strings vs. numbers)

Some intentional edge cases remain, such as empty string equals zero
and disregarding trailing / leading blanks. Please don’t nitpick and
spare me the fundamentalism, plus discussing whether discussing the
discussing qualifies as fundamentalism :-)

history.txt

@@ -2010,3 +2010,4 @@ ______
 132226
 ------
 * Cloud: fixed #125 (encode email address when signing up), thanks, Nathan!
+* Threads: fixed #207 (stricter comparison of strings vs. numbers). Some edge cases remain, such as empty string equals zero and disregarding trailing / leading blanks. These are intentional. Please don’t nitpick and spare me the fundamentalism :-)

threads.js

@@ -83,7 +83,7 @@ ArgLabelMorph, localize, XML_Element, hex_sha512*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.threads = '2013-October-17';
+modules.threads = '2013-November-26';
 
 var ThreadManager;
 var Process;
@@ -98,8 +98,8 @@ function snapEquals(a, b) {
         }
         return false;
     }
-    var x = parseFloat(a),
+    var x = +a;
-        y = parseFloat(b);
+        y = +b;
     if (isNaN(x) || isNaN(y)) {
         x = a;
         y = b;