Fix clipboard copy in new UI.

ClipboardJS is initialised once in the bundle for class="copy",
not initialised on each page that uses it.

modules/core/templates/show_metadata.twig

@@ -4,7 +4,7 @@
     <div class="code-box">
         <div class="code-box-title">
             <h3>{{ 'Metadata'|trans }}</h3>
-            <button data-clipboard-target="#metadata" id="btn{{ loop.index }}" class="pure-button right clipboard-btn">
+            <button data-clipboard-target="#metadata" id="btn{{ loop.index }}" class="pure-button right clipboard-btn copy">
                 <span class="fa fa-copy"></span>
             </button>
         </div>

templates/error.twig

@@ -19,7 +19,7 @@
         <p>{{ '{errors:report_trackid}' | trans }}</p>
         <div class="pure-button-group two-elements" role="group">
             <label class="pure-button hollow" disabled><pre id="trackid">{{ error.trackId }}</pre></label>
-            <button data-clipboard-target="#trackid" id="btntrackid" class="pure-button clipboard-btn">
+            <button data-clipboard-target="#trackid" id="btntrackid" class="pure-button clipboard-btn copy">
                 <i class="fa fa-copy"></i>
             </button>
         </div>

templates/metadata-converter.twig

@@ -31,7 +31,7 @@
     <div class="code-box">
         <div class="code-box-title">
             <h3> {{ type }}</h3>
-            <button data-clipboard-target="#metadata{{ loop.index }}" id="btn{{ loop.index }}" class="pure-button right clipboard-btn">
+            <button data-clipboard-target="#metadata{{ loop.index }}" id="btn{{ loop.index }}" class="pure-button right clipboard-btn copy">
                 <i class="fa fa-copy"></i>
             </button>
         </div>

templates/metadata.twig

@@ -8,7 +8,7 @@
     <p>{{ 'You can get the metadata xml on a dedicated URL:' | trans }}</p>
     <div class="input-group">
         <pre id="metadataurl" class="input-left">{{ metaurl }}</pre>
-        <button data-clipboard-target="#metadataurl" id="btnurl" class="pure-button right clipboard-btn">
+        <button data-clipboard-target="#metadataurl" id="btnurl" class="pure-button right clipboard-btn copy">
             <span class="fa fa-copy"></span>
         </button>
     </div>
@@ -18,7 +18,7 @@
     <div class="code-box">
         <div class="code-box-title">
     <p>{{ 'In SAML 2.0 Metadata XML format:' | trans }}</p>
-            <button data-clipboard-target="#xmlmetadata" id="btnxml" class="pure-button right clipboard-btn">
+            <button data-clipboard-target="#xmlmetadata" id="btnxml" class="pure-button right clipboard-btn copy">
                 <span class="fa fa-copy"></span>
             </button>
         </div>
@@ -30,7 +30,7 @@
     <div class="code-box">
         <div class="code-box-title">
     <p>{{ 'In SimpleSAMLphp flat file format - use this if you are using a SimpleSAMLphp entity on the other side:' | trans }}</p>
-            <button data-clipboard-target="#phpmetadata" id="btnphp" class="pure-button right clipboard-btn">
+            <button data-clipboard-target="#phpmetadata" id="btnphp" class="pure-button right clipboard-btn copy">
                 <span class="fa fa-copy"></span>
             </button>
         </div>