Add instructions to restore a token file from an offline Lotus node.

Did you find a bug, typo or other issue in an item of Filecoin documentation? Please use this template to let us know!

**URL of the page in question:**
_e.g. https://docs.filecoin.io/introduction/usage/_

https://docs.filecoin.io/get-started/lotus/send-and-receive-fil/#exporting-and-importing-addresses

**What's wrong with this page?**
_Please be as specific as possible. If relevant, screenshots are helpful!_

I needed on more step to restor wallet from an offline node. I had to restore the token file too.

**What would you like to have changed/amended/fixed in order to make things right?**
_Again, the more specific you are, the easier/faster fixing this item can be._

Add the restore token file step or the appropriate step

**Would you be interested in helping fix this page?**
_If yes, that would be wonderful! Feel free to create a PR against this new issue, and it'll get reviewed right away._
Yes, but im not sure of my solution

**Is there any other feedback you'd like to share about Filecoin docs?**