Returning function result

[wolph]

With this fix the decorator will return the result from the original function so it can be used as a drop-in decorator for functions that return a value.

[junnaka51]

@wolph Thank you so much! :)

[wolph]

I've got a few other suggestions as well if you're interested.

1. Add the median result (or even configurable 50%, 90%, etc.)
2. Add the option to skip the first or first few iterations to warm up. In the case of numba the first iteration is slow due to compilation.

[junnaka51]

@wolph
Thank you for the suggestions! The both sound reasonable :)

[wolph]

I've created a new pull request that incorporate these changes as well :)