Removed OS, manufacturer and category creation and edition.
	modified:   PCnstein/urls.py
	modified:   PCnsteinapp/globdata.py
	modified:   PCnsteinapp/templates/categories.html
	modified:   PCnsteinapp/templates/manufacturers.html
	modified:   PCnsteinapp/templates/oss.html
	modified:   PCnsteinapp/views.py