fixed tests

The get method was async some time ago. After this was changed to sync
the tests were not adapted and no assertion was executed.

test/shared/store/memory_store.test.js

@@ -9,39 +9,42 @@ describe('MemoryStore', function() {
   });
 
   it("should undefined for missing keys", function() {
-    store.get('foobar', function(err, value) {
-      should.equal(value, void 0);
-    });
+    var value = store.get('foobar');
+    should.equal(value, void 0);
   });
 
   it("should set and get a key + value", function() {
+    var value;
+
     store.set('cached_value', 42);
-    store.get('cached_value', function(err, value) {
-      should.equal(value, 42);
-    });
+    value = store.get('cached_value');
+    should.equal(value, 42);
+
     store.set('cached_value', 'new value');
-    store.get('cached_value', function(err, value) {
-      should.equal(value, 'new value');
-    });
+    value = store.get('cached_value');
+    should.equal(value, 'new value');
   });
 
   it("should be able to clear a key", function() {
+    var value;
+
     store.set('somethin', 'some value');
     store.clear('somethin');
-    store.get('somethin', function(err, value) {
-      should.equal(value, void 0);
-    });
+    value = store.get('somethin');
+
+    should.equal(value, void 0);
   });
 
   it("should be able to expire a key", function(done) {
+    var value;
+
     store.set('will_expire', '1234', 0.01);
-    store.get('will_expire', function(err, value) {
-      should.equal(value, '1234');
-    });
+    value = store.get('will_expire');
+    should.equal(value, '1234');
+
     setTimeout(function() {
-      store.get('will_expire', function(err, value) {
-        should.equal(value, void 0);
-      });
+      value = store.get('will_expire');
+      should.equal(value, void 0);
       done();
     }, 11);
   });