Wrap LoginActivity in ScrollView to account for small screens and landscape mode.

app/src/main/res/layout/activity_login.xml

@@ -1,9 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-  xmlns:app="http://schemas.android.com/apk/res-auto"
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
-  android:background="@color/colorPrimary"
+  android:background="@color/colorPrimary">
+
+  <LinearLayout xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
     android:gravity="center"
     android:orientation="vertical"
     android:padding="32dp">
@@ -98,4 +101,6 @@
       android:backgroundTint="@color/colorAccent"
       android:text="@string/login_submit"
       android:textColor="@color/whiteWhileLight" />
-</LinearLayout>
+  </LinearLayout>
+
+</ScrollView>