Add a documentation bbolt CLI `surgery` sub-command.

[ishan16696]

Please add a doc to play around with bbolt CLI surgery sub-command, so that user can itself fix the bbolt db in case of corruption.

    surgery     perform surgery on bbolt database

cc @ahrtr

[ishan16696]

I can work on it but I may need some help. Please feel free to assign me on this issue if this doc requirement is accepted.

cc @ahrtr @jmhbnz @serathius

[ivanvc]

If you're up to contributing to this, having more and better documentation is always good, and contributions are welcome :)

/assign @ishan16696