Use haven for GDPR popup instead of cookieconsent

Haven is newer and more well maintained (and also it is actually
open source instead of open core with an upsell to a paid subscrip-
tion). Haven is configured to be 100% *opt-in* for Google Analytics,
which means it does not load or send a hit until the user agrees.

This is mostly a drop-in replacement, but translations need to make
sure the following strings are updated:

- cookieAccept
- cookieDecline

layouts/partials/cookie-consent.html

@@ -1,28 +1,38 @@
-{{ $cookieConsentStyle := resources.Get "css/cookieconsent.min.css" | resources.Fingerprint }}
-<link href="{{ $cookieConsentStyle.Permalink }}" rel="stylesheet" type="text/css"{{ if not .Site.Params.disable_sri }} integrity="{{ $cookieConsentStyle.Data.Integrity }}" crossorigin="anonymous"{{ end }}>
-{{ $cookieConsentScript := resources.Get "js/cookieconsent.min.js" | resources.Fingerprint }}
-<script src="{{ $cookieConsentScript.Permalink }}"{{ if not .Site.Params.disable_sri }} integrity="{{ $cookieConsentScript.Data.Integrity }}" crossorigin="anonymous"{{ end }} async></script>
+{{ $cookieConsentScript := resources.Get "js/haven.umd.min.js" | resources.Fingerprint }}
+<script src="{{ $cookieConsentScript.Permalink }}"{{ if not .Site.Params.disable_sri }} integrity="{{ $cookieConsentScript.Data.Integrity }}" crossorigin="anonymous"{{ end }}></script>
 
 <script>
-window.addEventListener("load", function(){
-  window.cookieconsent.initialise({
-    "palette": {
-      "popup": {
-        "background": "#428bca",
-        "text": "#ffffff"
-      },
-      "button": {
-        "background": "#f71559"
-      }
+Haven.create({
+    notification: {
+        policyUrl: "{{ .Site.Params.cookie_consent_info_url | absURL }}",
+        styles: {
+            background: '#428bca',
+            textColor: '#ffffff',
+            buttonBackgroundColor: '#f71559',
+            buttonTextColor: '#ffffff',
+        },
     },
-    "content": {
-      "message": '{{ i18n "cookieMessage" }}',
-      "dismiss": '{{ i18n "cookieDismiss" }}',
-      "link": '{{ i18n "cookieLink" }}',
-      "href": "{{ .Site.Params.cookie_consent_info_url | absURL}}"
+    translations: {
+      {{ .Lang }}: {
+            notification: {
+                policy: '{{ i18n "cookieLink" }}',
+                message: '{{ i18n "cookieMessage" }}',
+                accept: '{{ i18n "cookieAccept" }}',
+                decline: '{{ i18n "cookieDecline" }}',
+            }
+        },
     },
-    "position": "bottom-right"
-  })});
+    services: [
+        {
+            name: 'google-analytics',
+            options: {
+                    id: '{{ .Site.Params.googleAnalytics }}',
+            },
+            purposes: ['analytics'],
+            inject: true,
+        }
+    ]
+});
 </script>
 
 {{- /* vim: set ts=2 sw=2 et: */}}