Set default build option to be debug. Fix two unclosed debug regions.

Author: bagnell

Source/Core/Matrix2.js

@@ -570,7 +570,7 @@ define([
         if (!defined(matrix)) {
             throw new DeveloperError('matrix is required');
         }
-        //excludeEnd('debug');
+        //>>includeEnd('debug');
 
         var column0Row0 = matrix[0];
         var column0Row1 = matrix[2];

Source/Core/Matrix4.js

@@ -1847,7 +1847,7 @@ define([
         if (typeof epsilon !== 'number') {
             throw new DeveloperError('epsilon is required and must be a number');
         }
-        //excludeEnd('debug');
+        //>>includeEnd('debug');
 
         return (left === right) ||
                 (defined(left) &&

Tools/build.js

@@ -3,6 +3,6 @@
     useStrict : true,
     optimizeCss : 'standard',
     pragmas : {
-        debug : false
+        debug : true
     }
 })