Merge pull request #1 from nasonfish/master

utils: When serializing a dict, don't have the for loop _unpack_ the key, have it get the key/value.
service: prune unpaid reservations after 3 hours
invoice: add finalize API endpoint
invoice: add API to add a lineitem to an invoice.
profile: add API endpoint to generate a blank invoice for a user
invoice: finish custom invoice UI stuff
invoice: make the invoice view less retarded
vps/models: import logic for multiple classes of cpu pool
cputhrottle: set limit to 60%
signup: new signup experience, part 1
vps: add plumbing for specifying a nickname at creation time
vps: signup experience part 2
vps: signup experience, part 3
service: allow sending other letters than the non-payment one for suspension
contrib/antitor: send out a proper e-mail detailing our TOR policy
vps: fix exception when no ISO media is selected
invoice: display company mailing address if configured
preferences: allow updating all known contact fields in cloudware
invoice: display contact information on printed invoices
vps: implement region-wide ip ranges