Added tag to Untranslatable terms (#15)

Author: LucaBlackDragon

Diff for: GLOSSARY.md

@@ -8,6 +8,7 @@ Glossary of the translations of technical and React-specific terms.
 - browser
 - client
 - server
+- tag
 
 # Common Translations
 
@@ -30,4 +31,4 @@ Here's a list of terms that require discussion/agreement, with a link to the iss
 - `React component type` (#7)
 - `refactor` (#9)
 - `event handler` (#10)
-- `event listener` (#10)
+- `event listener` (#10)