fingerprint CSS and JS, set one week browser cache

...and LOTS of tidying partials

layouts/index.webmanifest

@@ -0,0 +1,22 @@
+{{- $android512 := resources.Get "img/android-chrome-512x512.png" -}}
+{{- $android192 := resources.Get "img/android-chrome-192x192.png" -}}
+{
+  "name": "{{ .Site.Title }}",
+  "short_name": "{{ .Site.Params.domain }}",
+  "icons": [
+    {
+      "src": "{{ $android512.Permalink }}",
+      "sizes": "512x512",
+      "type": "image/png"
+    },
+    {
+      "src": "{{ $android192.Permalink }}",
+      "sizes": "192x192",
+      "type": "image/png"
+    }
+  ],
+  "start_url": "{{ .Site.BaseURL }}",
+  "display": "browser",
+  "background_color": "#ffffff",
+  "theme_color": "#0e6dc2"
+}