Ditch the pregenerated static db

Now that we're storing onetime challenges in a db anyway,
the pregenerated static challenge db becomes redundat
(which is a nice word for silly).
Merge remote-tracking branch 'upstream/master'

Conflicts:
	README.md
Merge pull request #3 from thedod/master

Tested my fork on whatmail/tipwire and nothing seems broken, so let's go for it :)