replace q method calls with bluebird ones

```
find src test -name '*.js' |
    xargs perl -i -pe 's/q\.(all|defer|reject|delay|try|isFulfilled)\(/Promise.$1(/'
```

test/components/views/dialogs/InteractiveAuthDialog-test.js

@@ -110,7 +110,7 @@ describe('InteractiveAuthDialog', function () {
             );
 
             // let the request complete
-            return q.delay(1);
+            return Promise.delay(1);
         }).then(() => {
             expect(onFinished.callCount).toEqual(1);
             expect(onFinished.calledWithExactly(true, {a:1})).toBe(true);

test/components/views/rooms/MessageComposerInput-test.js

@@ -47,7 +47,7 @@ describe('MessageComposerInput', () => {
         // warnings
         // (please can we make the components not setState() after
         // they are unmounted?)
-        Q.delay(10).done(() => {
+        Promise.delay(10).done(() => {
             if (parentDiv) {
                 ReactDOM.unmountComponentAtNode(parentDiv);
                 parentDiv.remove();