[IMP] theme_kea: update the theme

This commit updates the theme to improve the design
with background shapes, new pictures and new custom snippets.

task-2591476

Part-of: odoo/design-themes#36

theme_kea/views/snippets/s_image_gallery.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<odoo>
+
+<template id="s_images_wall" inherit_id="website.s_images_wall">
+    <!-- Section -->
+    <xpath expr="//section" position="attributes">
+        <attribute name="class" add="pt96 pb96" remove="pt24 pb24" separator=" "/>
+    </xpath>
+</template>
+
+</odoo>