fix: add "no-prototype-builtins" eslint-rule and fix all occurences

spec/compiler.js

@@ -59,7 +59,7 @@ describe('compiler', function() {
         Handlebars.compile(' \n  {{#if}}\n{{/def}}')();
         equal(true, false, 'Statement must throw exception. This line should not be executed.');
       } catch (err) {
-        equal(err.propertyIsEnumerable('column'), true, 'Checking error column');
+        equal(Object.prototype.propertyIsEnumerable.call(err, 'column'), true, 'Checking error column');
       }
     });
 

spec/regressions.js

@@ -211,12 +211,12 @@ describe('Regressions', function() {
         // It's valid to execute a block against an undefined context, but
         // helpers can not do so, so we expect to have an empty object here;
         for (var name in this) {
-          if (this.hasOwnProperty(name)) {
+          if (Object.prototype.hasOwnProperty.call(this, name)) {
             return 'found';
           }
         }
         // And to make IE happy, check for the known string as length is not enumerated.
-        return (this == 'bat' ? 'found' : 'not');
+        return (this === 'bat' ? 'found' : 'not');
       }
     };