Add github link to help text

EditorHelp.js

@@ -67,6 +67,13 @@ class EditorHelp extends EditorEntryBase {
     this.addLine();
     this.addKey('m');
     this.addText('Next theme      ');
+
+    this.addLine();
+
+    this.addLine();
+    this.addLink(
+        'GitHub',
+        'https://github.com/firestuff/architype/blob/master/README.md');
   }
 
   addLine() {
@@ -90,6 +97,13 @@ class EditorHelp extends EditorEntryBase {
     }
   }
 
+  addLink(text, href) {
+    let a = document.createElement('a');
+    a.href = href;
+    a.innerText = text;
+    this.line_.appendChild(a);
+  }
+
   afterDomAdd() {
     this.elem_.focus();
   }

architype.css

@@ -144,6 +144,7 @@ body {
 }
 
 .editor li.help > div {
+  margin-top: 2px;
   min-height: 10px;
 }
 
@@ -170,6 +171,10 @@ body {
   margin: 5px;
 }
 
+.editor li.help a {
+  color: var(--text);
+}
+
 .editor li:focus {
   border-left: 10px solid var(--focus) !important;
 }