app: update application menu

Use only application wide actions in the menu, as stated in GNOME HIG
Migrated to use GtkBuilder files

data/Makefile.am

@@ -18,6 +18,7 @@ gsettings_SCHEMAS = $(gsettingsschema_in_files:.xml.in=.xml)
 EXTRA_DIST=                     \
   gnome-calendar.desktop        \
   calendar.gresource.xml        \
+  ui/menus.ui                   \
   ui/nav_bar.ui                 \
   ui/new-event.ui               \
   ui/viewport.ui                \

data/calendar.gresource.xml

@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <gresources>
   <gresource prefix="/org/gnome/calendar">
+    <file alias="menus.ui" compressed="true" preprocess="xml-stripblanks">ui/menus.ui</file>
     <file alias="nav_bar.ui" compressed="true" preprocess="xml-stripblanks">ui/nav_bar.ui</file>
     <file alias="viewport.ui" compressed="true" preprocess="xml-stripblanks">ui/viewport.ui</file>
     <file alias="new-event.ui" compressed="true" preprocess="xml-stripblanks">ui/new-event.ui</file>

data/ui/menus.ui

@@ -0,0 +1,29 @@
+<?xml version="1.0"?>
+<interface>
+  <menu id="appmenu">
+    <section>
+      <item>
+        <attribute name="label" translatable="yes">_New</attribute>
+        <attribute name="action">app.new</attribute>
+        <attribute name="accel">&lt;Primary&gt;n</attribute>
+      </item>
+      <item>
+        <attribute name="label" translatable="yes">_Search...</attribute>
+        <attribute name="action">app.search</attribute>
+        <attribute name="accel">&lt;Primary&gt;f</attribute>
+      </item>
+    </section>
+    <section>
+      <item>
+        <attribute name="label" translatable="yes">_About</attribute>
+        <attribute name="action">app.about</attribute>
+        <attribute name="accel">&lt;Primary&gt;a</attribute>
+      </item>
+      <item>
+        <attribute name="label" translatable="yes">_Quit</attribute>
+        <attribute name="action">app.quit</attribute>
+        <attribute name="accel">&lt;Primary&gt;q</attribute>
+      </item>
+    </section>
+  </menu>
+</interface>