Extract error rendering

assets/templates/html/base.html.tmpl

@@ -2,7 +2,7 @@
 <html>
     <head>
         <meta charset="utf-8">
-        <title>{{block "title" .}}{{end}}</title>{{block "head-append" .}}{{end}}
+        <title>{{block "title" .}}rushlink{{end}}</title>{{block "head-append" .}}{{end}}
     </head>
     <body>
         {{block "body" .}}{{end}}

assets/templates/html/error.html.tmpl

@@ -0,0 +1,8 @@
+{{define "title"}}
+Error - rushlink
+{{end}}
+{{define "body"}}
+<pre>
+{{.Message}}
+</pre>
+{{end}}

assets/templates/txt/error.txt.tmpl

@@ -0,0 +1 @@
+{{.Message}}