Load the Housekeeper class

[tristanlins]

Situation:

• plugin is installed
• plugin get uninstelled

Result:

• Housekeeper class not found

The plugin is loaded, register the Housekeeper, but if the plugin get uninstalled the housekeeper does not exist anymore and a "Housekeeper class not found" is thrown.

Solutin:

• do a class_exist("...\Housekeeper"); if the plugin is loaded, so the class is loaded into memory before it gets uninstalled.