Add night drawables and change drawables name

This renames the drawable files removes the color from the name

Author: kunall17

app/src/main/java/com/zulip/android/activities/MessageListFragment.java

@@ -139,9 +139,9 @@ public View onCreateView(LayoutInflater inflater, ViewGroup container,
 
         emptyTextView = (TextView) view.findViewById(R.id.emptyList);
         if (filter != null && ((AppCompatActivity) getActivity()).getSupportActionBar() != null)
-            ((AppCompatActivity) getActivity()).getSupportActionBar().setHomeAsUpIndicator(R.drawable.ic_arrow_back_black_24dp);
+            ((AppCompatActivity) getActivity()).getSupportActionBar().setHomeAsUpIndicator(R.drawable.ic_arrow_back_24dp);
         else
-            ((AppCompatActivity) getActivity()).getSupportActionBar().setHomeAsUpIndicator(R.drawable.ic_menu_black_24dp);
+            ((AppCompatActivity) getActivity()).getSupportActionBar().setHomeAsUpIndicator(R.drawable.ic_menu_24dp);
         recyclerView = (RecyclerView) view.findViewById(R.id.recyclerView);
         linearLayoutManager = new LinearLayoutManager(getContext());
         recyclerView.setLayoutManager(linearLayoutManager);

app/src/main/java/com/zulip/android/activities/ZulipActivity.java

@@ -270,7 +270,7 @@ protected void onCreate(Bundle savedInstanceState) {
         getSupportActionBar().setDisplayHomeAsUpEnabled(true);
         getSupportActionBar().setHomeButtonEnabled(true);
         getSupportActionBar().setTitle(R.string.app_name);
-        getSupportActionBar().setHomeAsUpIndicator(R.drawable.ic_menu_black_24dp);
+        getSupportActionBar().setHomeAsUpIndicator(R.drawable.ic_menu_24dp);
         streamActv = (AutoCompleteTextView) findViewById(R.id.stream_actv);
         topicActv = (AutoCompleteTextView) findViewById(R.id.topic_actv);
         messageEt = (AutoCompleteTextView) findViewById(R.id.message_et);