Merge branch '354-rename-annotations-to-index---systems-frontend' into 'master'

renamed "annotations" to "index" in userNav (#354)

Closes #354

See merge request !116

src/i18n/en/index.js

@@ -113,7 +113,7 @@ export default {
     recursive: 'Apply to all contained annotations and media',
     add_group: 'Add Group',
     add_term: 'Add Term',
-    annotations: 'Annotations',
+    annotations: 'Index',
     annotation_body: 'Annotation text',
     accept_terms: 'I accept the Terms and Conditions',
     author: 'Author',