Add shortcut for categories

web/static/shortcuts.js

@@ -277,6 +277,7 @@ rrh.shortcuts.addGroup(new ShortcutGroup('Common', null, [
     new Shortcut('g', $$('.top-bar__highlight-link'), 'First 9 header links'),
     new Shortcut('g h', '/', 'Home'),
     new Shortcut('g l', '/list/', 'List of hyphae'),
+    new Shortcut('g c', '/category/', 'List of Categories'),
     new Shortcut('g r', '/recent-changes/', 'Recent changes'),
     new Shortcut('g u', $('.auth-links__user-link'), 'Your profile′s hypha'),
     new Shortcut(['?', isMac ? 'Meta+/' : 'Ctrl+/'], openHelp, 'Shortcut help', { force: true }),