have criterion analyse user supplied timing data?

Is it possible to use the criterion analysis and reporting functions on timing data that I supply?

I've tried hacking the criterion code to get this simple example to work:

```
{-# LANGUAGE RecordWildCards #-}

import Criterion.Monad (withConfig)
import Criterion.Main (defaultConfig)
import Control.Monad.Except
import Criterion.Internal
import Criterion.Types
import qualified Data.Vector as V

theData = [ 2.0, 2.1, 2.2, 2.1, 2.1, 2.15, 2.09 ] :: [Double]

mkMeas t = Measured t t cycles 1 0 0 0 0 0 0 0
where cycles = floor (1000000*t)

main = do
let ms = map mkMeas theData
withConfig defaultConfig $ do
r <- analyseOne 1 "foo" (V.fromList ms)
liftIO $ putStrLn "done"
```

The changes I made to the criterion source to get this to "work" were:
- export `analyseOne` from `Criterion.Internal`
- in `analyseSample` set `overhead` to a constant (0.00001)

However, this reports a negative value for "time":

```
time -9.4833e15 s (-9.6763e15 s .. -9.2838e15 s)
-3.497 R² (-9782.939 R² .. -1.158 R²)
mean 2.123 s (2.097 s .. 2.175 s)
std dev 43.20 ms (21.60 ms .. 58.54 ms)
variance introduced by outliers: 12% (moderately inflated)
```

Am I on the right track, or am I missing something? Thanks!