docs: updated milestones

***NO_CI***

README.md

@@ -84,7 +84,7 @@ Current and upcoming milestones *(major features only, see the [changelog](https
   - MongoDB is being phased out in favor of PostgreSQL + Redis. An upgrade tool will be provided to migrate existing data to the new system.
   - Node.js 8.9 LTS or later is now the minimum supported version.
 
-**2.0 Milestones**:
+**2.0 Milestone**:
 - [x] GraphQL API
 - [x] Migrate to PostgreSQL + Redis datastore
 - [x] Telemetry for analytics and crash reporting (Optional and fully anonymized)
@@ -107,15 +107,17 @@ Current and upcoming milestones *(major features only, see the [changelog](https
 - [ ] Persist system settings to database instead of file-based
 - [ ] User Groups + Better permissions management
 - [ ] Tags per document / folder
+
+:rocket: = Currently in development
+
+**2.1 Milestone**
 - [ ] Comments / Discussion per document
 - [ ] Profile page per user
 - [ ] Preview changes directly from the editor, without saving
 - [ ] Diagrams as code (Mermaid module)
 - [ ] Insert Link modal in Markdown Editor
 
-:rocket: = Currently in development
-
-**TBD Milestones**
+**TBD Milestone**
 - [ ] Better simultaneous user editing handling
 - [ ] High Availability support (multiple concurrent instances)