Fix broken add interface view

a "startsWith" was inserted by commit 1a2f3786
This is the javascript syntax. In Python, it should be lowercase
"startswith"...

app/network/views.py

@@ -126,7 +126,7 @@ def edit_host(name):
 @login_groups_accepted('admin', 'create')
 def create_interface(hostname):
     host = models.Host.query.filter_by(name=hostname).first_or_404()
-    random_mac = host.device_type.name.startsWith('Virtual')
+    random_mac = host.device_type.name.startswith('Virtual')
     form = InterfaceForm(request.form, host_id=host.id, interface_name=host.name,
                          random_mac=random_mac)
     if form.validate_on_submit():