had to work around a bunch of viper nonsense with handling string slices
changed the validator.Check to use reflect.DeepEqual
fixed a bug where env vars need to be reset between tests
had to change the structure of pilosa.config to enable the passing of hosts as a
slice of strings (it was a slice of structs which each just contained the string
host.) so we lose some generality, but we weren't using it anyway.
1. fixed a couple bugs with config file reading.
2. made cmd.Serve a global variable so tests could inspect it.
3. added table style testing for pilosa server
4. added the ability to stop server programmatically which also causes the cobra
command running it to return.