Added modifying capability to components and manufacturers, checking if the user is in the permissions group (but not if the user is the same who has created the object).
Made some forms more pretty (creation and modification of thingies).
Added the needed urls and globdata to do this.
Placeholder -> the modify link is in the global page, not in every component/manufacturer.
	modified:   PCnstein/urls.py
	modified:   PCnsteinapp/globdata.py
	modified:   PCnsteinapp/templates/components.html
	modified:   PCnsteinapp/templates/create.html
	modified:   PCnsteinapp/templates/manufacturers.html
	new file:   PCnsteinapp/templates/modify.html
	modified:   PCnsteinapp/views.py