[Rev 01] RFR: 314: Add help command to git-pr

[Erik Helin]

> Hi all,
> 
> please review this patch that enhances the default `help` command for `git pr`
> by quite a bit. `git pr` will now be default list the usage and flags for all
> available sub-commands. A user can now also run `git pr help <sub-command>`,
> e.g. `git pr help set`:
> 
> $ git pr help set
> Usage: git pr set [<ID>]
> Flags:
>   -u, --username NAME   Username on host
>   -r, --remote NAME     Name of remote, defaults to 'origin'
>       --assignees LIST  Comma separated list of assignees
>       --title MESSAGE   The title of the pull request
>       --open            Set the pull request's state to open
>       --closed          Set the pull request's state to closed
>       --body            Set the body of the pull request
>       --no-draft        Mark the pull request as not draft
>       --verbose         Turn on verbose output
>       --debug           Turn on debugging output
>       --version         Print the version of this tool
> 
> Testing:
> - Manual testing of `git pr` on Linux x64
> 
> Thanks,
> Erik

Erik Helin has updated the pull request incrementally with one additional commit since the last revision:

  Better formatting

-------------

Changes:
  - all: https://git.openjdk.java.net/skara/pull/521/files
  - new: https://git.openjdk.java.net/skara/pull/521/files/038c21f9..ce0731df

Webrevs:
 - full: https://webrevs.openjdk.java.net/skara/521/webrev.01
 - incr: https://webrevs.openjdk.java.net/skara/521/webrev.00-01

  Stats: 8 lines in 1 file changed: 1 ins; 1 del; 6 mod
  Patch: https://git.openjdk.java.net/skara/pull/521.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/521/head:pull/521

PR: https://git.openjdk.java.net/skara/pull/521