Fix back navigation. Add 'discovery' drawer item.

src/syng_im/android/core.cljs

@@ -30,7 +30,7 @@
                        ;; this listener and handle application's closing
                        ;; in handlers
                        (let [stack (subscribe [:navigation-stack])]
-                         (when (< 1 (count stack))
+                         (when (< 1 (count @stack))
                            (dispatch [:navigate-back])
                            true)))]
     (add-event-listener "hardwareBackPress" new-listener)))

src/syng_im/components/drawer.cljs

@@ -50,6 +50,9 @@
                 :handler (fn []
                            ;; TODO not implemented
                            )}]
+    [menu-item {:name    "Discovery"
+                :handler (fn []
+                           (dispatch [:navigate-to :discovery]))}]
     [menu-item {:name    "Contacts"
                 :handler (fn []
                            (dispatch [:show-contacts navigator]))}]

src/syng_im/db.cljs

@@ -4,7 +4,7 @@
 ;; schema of app-db
 (def schema {:greeting s/Str})
 
-(def default-view :discovery)
+(def default-view :chat-list)
 
 ;; initial state of app-db
 (def app-db {:greeting             "Hello Clojure in iOS and Android!"