Allow for the db.json file to be committed but none of the other node_modules

Further update following testing

Author: seamuslee001

.gitignore

@@ -4,4 +4,5 @@ composer.phar
 # Commit your application's lock file http://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file
 # You may choose to ignore a library lock file http://getcomposer.org/doc/02-libraries.md#lock-file
 # composer.lock
-node_modules/
+node_modules/mime-db/*
+!node_modules/mime-db/db.json