Implements the "git checkout" subcommand of git for variations: git checkout [-q] [-f] [-m] [ ] git checkout [-q] [-f] [-m] --detach [ ] git checkout [-q] [-f] [-m] [--detach] git checkout [-q] [-f] [-m] [[-b|-B|--orphan] ] [ ]
(c *Client, opts CheckoutOptions, commit Commitish)
source not stored for this graph (policy: none)