update banner to use RTD projects subdirs (ansible#3145)

(cherry picked from commit 481c896)

Author: oraNod

docs/docsite/.templates/banner.html

@@ -1,7 +1,7 @@
 {% if is_eol %}
 {# Creates a banner at the top of the page for EOL versions. #}
 <div id='banner' class='Admonition caution'>
-  <p>You are reading an unmaintained version of the Ansible community documentation. Unmaintained Ansible versions can contain security vulnerabilities (CVEs). Please upgrade to a maintained version. See <a href="/ansible/latest/">the latest Ansible documentation</a>. Note that this statement does not apply to Red Hat Ansible Automation Platform subscriptions. See the <a href="https://access.redhat.com/support/policy/updates/ansible-automation-platform">Ansible Automation Platform Life Cycle</a>.</p>
+  <p>You are reading an unmaintained version of the Ansible community documentation. Unmaintained Ansible versions can contain security vulnerabilities (CVEs). Please upgrade to a maintained version. See <a href="https://docs.ansible.com/projects/ansible/latest/">the latest Ansible documentation</a>. Note that this statement does not apply to Red Hat Ansible Automation Platform subscriptions. See the <a href="https://access.redhat.com/support/policy/updates/ansible-automation-platform">Ansible Automation Platform Life Cycle</a>.</p>
 </div>
 {% else %}
   <script>
@@ -27,7 +27,7 @@
     // Create a banner if we're not on the official docs site
     if (location.host == "docs.testing.ansible.com") {
       document.write('<div id="testing_banner_id" class="admonition important">' +
-                     '<p>This is the testing site for Ansible Documentation. Unless you are reviewing pre-production changes, please visit the <a href="https://docs.ansible.com/ansible/latest/">official documentation website</a>.</p> <p></p>' +
+                     '<p>This is the testing site for Ansible Documentation. Unless you are reviewing pre-production changes, please visit the <a href="https://docs.ansible.com/projects/ansible/latest/">official documentation website</a>.</p> <p></p>' +
                      '</div>');
     }
     {% if available_versions is defined %}
@@ -45,7 +45,7 @@
         msg += 'This is the <b>latest</b> (stable) Ansible community documentation. For Red Hat Ansible Automation Platform subscriptions, see <a href="https://access.redhat.com/support/policy/updates/ansible-automation-platform">Life Cycle</a> for version details.';
       } else if (startsWith(current_url_path, "/ansible/2.9/")) {
         msg += 'You are reading the latest Red Hat released version of the Ansible documentation. Community users can use this version, or select <b>latest</b> from the version selector to the left for the most recent community version.';
-      } else if (startsWith(current_url_path, "/ansible/devel/")) {
+      } else if (startsWith(current_url_path, "/projects/ansible/devel/")) {
         /* temp extra banner to advertise something */
         banner += extra_banner;