events: allow editing of all used values

1. Allow to change the date/time and
other relevant values of an event
on creation and after it was created.

2. Harmonize layout file names and
variable names.

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

@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:orientation="vertical"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:padding="20dp">
+
+    <EditText
+        android:id="@+id/notes_qty_edittext"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:lines="1"
+        android:inputType="number"
+        android:hint="@string/log_notes_dialog_qty_hint"
+        android:background="@drawable/textview_background"/>
+
+    <EditText
+        android:id="@+id/notes_edittext"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="10dp"
+        android:gravity="top"
+        android:lines="10"
+        android:hint="@string/log_notes_dialog_note_hint"
+        android:background="@drawable/textview_background"/>
+
+    <TextView
+        android:id="@+id/dialog_date_picker"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center"
+        android:layout_marginTop="20dp"/>
+
+</LinearLayout>