Update react-sdk and js-sdk dependencies

package.json

@@ -62,8 +62,8 @@
     "gfm.css": "^1.1.1",
     "highlight.js": "^9.0.0",
     "linkifyjs": "^2.1.3",
-    "matrix-js-sdk": "0.7.6",
-    "matrix-react-sdk": "0.8.7",
+    "matrix-js-sdk": "0.7.7-rc.1",
+    "matrix-react-sdk": "0.8.8-rc.1",
     "modernizr": "^3.1.0",
     "q": "^1.4.1",
     "react": "^15.4.0",