[Docs] Add posthog telemetry to docs (#577)

Allows creation of funnels and user journeys

docs/mkdocs.yml

@@ -144,6 +144,8 @@ nav:
 
 extra_css:
   - styles/global.css
+extra_javascript:
+  - scripts/posthog.js
 
 extra:
   analytics:

docs/src/scripts/posthog.js

@@ -0,0 +1,4 @@
+window.addEventListener("DOMContentLoaded", (event) => {
+    !function(t,e){var o,n,p,r;e.__SV||(window.posthog=e,e._i=[],e.init=function(i,s,a){function g(t,e){var o=e.split(".");2==o.length&&(t=t[o[0]],e=o[1]),t[e]=function(){t.push([e].concat(Array.prototype.slice.call(arguments,0)))}}(p=t.createElement("script")).type="text/javascript",p.async=!0,p.src=s.api_host+"/static/array.js",(r=t.getElementsByTagName("script")[0]).parentNode.insertBefore(p,r);var u=e;for(void 0!==a?u=e[a]=[]:a="posthog",u.people=u.people||[],u.toString=function(t){var e="posthog";return"posthog"!==a&&(e+="."+a),t||(e+=" (stub)"),e},u.people.toString=function(){return u.toString(1)+".people (stub)"},o="capture identify alias people.set people.set_once set_config register register_once unregister opt_out_capturing has_opted_out_capturing opt_in_capturing reset isFeatureEnabled onFeatureFlags getFeatureFlag getFeatureFlagPayload reloadFeatureFlags group updateEarlyAccessFeatureEnrollment getEarlyAccessFeatures getActiveMatchingSurveys getSurveys".split(" "),n=0;n<o.length;n++)g(u,o[n]);e._i.push([i,s,a])},e.__SV=1)}(document,window.posthog||[]);
+    posthog.init('phc_oENDjGgHtmIDrV6puUiFem2RB4JA8gGWulfdulmMdZP',{api_host:'https://app.posthog.com'})
+});