Reverting mysql to 2.1.1

- Unfortunately mysql has changed the way it handles the charset setting such that
it now causes encoding issues on many setups where 'utf8' is apparently not the
correct setting.
- We need to revert this upgrade until the issue is fixed or we have a way to handle
it nicely for our users.

package.json

@@ -65,7 +65,7 @@
         "xml": "0.0.12"
     },
     "optionalDependencies": {
-        "mysql": "2.5.2",
+        "mysql": "2.1.1",
         "pg.js": "3.6.2"
     },
     "devDependencies": {