JS Tracking code generator: new link to help page "Measuring domains and/or...

JS Tracking code generator: new link to help page "Measuring domains and/or subdomains" https://github.com/piwik/piwik/issues/9932

plugins/CoreAdminHome/templates/trackingCodeGenerator.twig

@@ -50,6 +50,7 @@
         <div class="form-group">
             <div class="form-help">
                 {{ 'CoreAdminHome_JSTracking_MergeSubdomainsDesc'|translate("x.<span class='current-site-host'>"~defaultReportSiteDomain~"</span>","y.<span class='current-site-host'>"~defaultReportSiteDomain~"</span>")|raw }}
+                {{ 'General_LearnMore'|translate(' (<a href="http://developer.piwik.org/guides/tracking-javascript-guide#measuring-domains-andor-sub-domains" rel="noreferrer"  target="_blank">', '</a>)')|raw }}
             </div>
             <label class="checkbox">
                 <input type="checkbox" id="javascript-tracking-all-subdomains"/>