Breaking changes with > 9.1.0

[gugu91]

Thanks for this awesome library, really grateful for all your work!

Just wanted to flag that this line is a breaking change from the standpoint of typescript.

The other breaking change is that BigNumber.dp() can now be null.

Thought I'd leave a tiny migration guide:

1. How to handle null dp?
2. What is the advised way of importing the full BigNumber type now?

[gugu91]

2. What is the advised way of importing the full BigNumber type now?

Just import the default export and everything should be ok

[gugu91]

1. How to handle null dp? Just check the value first (it's recommended you have strictNullChecks: true in your tsconfig.

const dp = value.dp()
if (dp === null) {
// NaN or Infinity
...
}