Option.getUnsafe does not raise

[agarwal]

The documentation of Option.getUnsafe gives the example:

Option.getUnsafe(None) // Raises an error

However, the following code does not raise. I see undefined printed to the console and no exception.

let x = Option.getUnsafe(None)
Js.log(j`$x`)

Why is there also an Option.getExn function? That has the expected behavior, so I'm using that for now.

[glennsl]

The documentation is wrong. "Unsafe" here means that it's unsoundly typed, i.e. that it may return a value that does not belong to its return type, in this case undefined, which does not belong to most types you can put in an option.

[glennsl]

Proposed fix in #131