Fix the bundle

[Fuzzyma]

Unfortunately I am forced to use the dist bundle to include the feature into my application (with a good old script tag).

I found that you populate the lib methods in a global index object. However, this is not only a not very intuitive name. The actual problem is, that the object is filled with values of undefined.

index: {
__esModule: true,
addedDiff: undefined,
deletedDiff: undefined,
detailedDiff: undefined,
diff: undefined,
updatedDiff: undefined
}

Please fix that since it stops me from using this package at all :/

PS: I know about the horror of maintaining old packages. However, since you seem to bundle the package with babel only, I can't really help with a quick PR. It would be cool though if you would find some spare time to work on this