Issue 5385 - Create Site Header Component for Help Center

includes/layout/header.tmpl

Index: includes/layout/header.tmpl
===================================================================
new file mode 100644
--- /dev/null
+++ b/includes/layout/header.tmpl
@@ -0,0 +1,30 @@
+<header id="site-header" class="navbar">
+  <div class="navbar-wrapper">
+    <h1 id="site-title">
+      {{ "index" | linkify() }}
+        <img src="/img/png/eyeo-help.png" srcset="/img/svg/eyeo-help.svg 2x" alt="{{ "eyeo Help" | translate("site-title", "Image alt text") }}">
+      </a>
+    </h1>
+
+    <button class="toggle-navbar-collapse unstyled phablet-and-mobile-only">
+      <img src="/img/png/search-icon.png" srcset="/img/svg/search-icon.svg 2x" alt="{{ "Toggle Search Bar" | translate("search-toggle-alt", "Image alt text") }}">
+    </button>
+
+    <div class="navbar-collapse">
+      <form id="search-form" action="https://duckduckgo.com" method="GET">
+        <label for="search" class="sr-only">{{ "Search Adblock Plus Help" | translate("search-form-label", "Input label") }}</label>
+        <input id="search" name="q" type="search" placeholder="{{ "Search Adblock Plus Help" | translate("search-form-label", "Input label") }}">
+        <input type="hidden" name="sites" value="adblockplus.org">
+        <button type="submit">
+          <img src="/img/png/search-icon.png" srcset="/img/svg/search-icon.svg 2x" alt="{{ "Search" | translate("search-icon-alt", "Image alt text") }}">
+        </button>
+      </form>
+
+      <nav id="product-website-link">
+        <a href="https://adblockplus.org/">
+          {{ "Adblock Plus" | translate("abp-product-link", "Link label") }}<img src="/img/png/external-icon.png" srcset="/img/svg/external-icon.svg 2x" alt="{{ "External link icon" | translate("external-link-icon", "Image alt text") }}">
+        </a>
+      </nav>
+    </div>
+  </div>
+</header>