add editor command to update database.yml; cleanup

doc/update/7.3-to-7.4.md

@@ -70,14 +70,17 @@ git diff origin/7-3-stable:config/gitlab.yml.example origin/7-4-stable:config/gi
 sudo -u git -H editor config/unicorn.rb
 ```
 
-#### Change nginx https settings
+#### Change Nginx HTTPS settings
 
 * HTTPS setups: Make `/etc/nginx/sites-available/gitlab-ssl` the same as https://gitlab.com/gitlab-org/gitlab-ce/blob/7-4-stable/lib/support/nginx/gitlab-ssl but with your setting
 
 #### MySQL Databases: Update database.yml config file
 
-* Add `collation: utf8_general_ci` to config/database.yml as seen in [config/database.yml.mysql](config/database.yml.mysql)
+* Add `collation: utf8_general_ci` to `config/database.yml` as seen in [config/database.yml.mysql](/config/database.yml.mysql)
 
+```
+sudo -u git -H editor config/database.yml
+```
 
 ### 5. Start application