initial vhosts implementation, #183

reduce copying of output lines

fix #262

optimizations related to #237

modes refactor, #255

have travis enforce gofmt, #253

eliminate dedicated RunSocketWriter goroutine

implement database auto-upgrades (#243)

fix #249

Stats for LUSERS logic now seperated, fixed params in LUSERS

Fixed LUSERS count not subtracting invisible users

update developing documentation

fix fakelag double-rate issue

Basically, fakelag was counting the time imposed by its own sleeps as though
the user had themselves paused for that amount of time. Therefore, if a user
sent a large number of consecutive commands, every other command would pause
for the expected throttle interval, but the subsequent command would be
processed instantly (you'd get two back-to-back commands). This resulted in
throttled users being able to send at double the expected rate.

Updates to channel persistence

* Placate `go vet`
* Reorder the `send` loop, clarify things a little