Add support of revert updating

[Eugene]

Is your feature request related to a problem? Please describe.
When I run ghacu -u by mistake I want to rollback the changes.

Describe the solution you'd like
As a solution, it could be implemented in the same way as maven does it. During upgrading Maven creates temporary file(s) that stores previous versions of tools, and when you run mvn versions:commit it removes temporary files. In ghacu we have LiteDB file where we store some information, so we can use it to store old versions and remove them as soon as we run ghacu --commit or something like that. If I run ghacu --revert, old versions should be back and records should be removed from LiteDB file.

Describe alternatives you've considered
If project under the versions control system, like git, it's possible to revert changes using git.

Additional context
N/A