RFR: git-pr-create: be explicit about CC:d mailing lists [v2]

[Erik Helin]

> Hi all,
> 
> please review this patch that makes `git pr create` much more explicit about the
> mailing lists that will be CC:d for the "RFR" email generated from a pull
> request. A user can now manually specify the mailing lists with `--cc` flag, for
> example:
> 
> $ git pr create --cc=hotspot-dev,build-dev
> 
> Furthermore, `git pr create` will now also prompt the user for confirmation
> about the selected mailing lists before proceeding:
> 
> $ git pr create --cc=hotspot-dev,build-dev
> You have chosen the following mailing lists to be CC:d for the "RFR" e-mail:
> - hotspot-dev at openjdk.java.net
> - build-dev at openjdk.java.net
> 
> Do you want to proceed with this mailing list selection? [Y/n]:
> 
> If a user does not specify `--cc`, then `git pr create` will display the mailing
> lists that were inferred based on the changes in the pull request:
> 
> The following mailing lists will be CC:d for the "RFR" e-mail:
> - build-dev at openjdk.java.net
> 
> Do you want to proceed with this mailing list selection? [Y/n]:
> 
> If a user specify `--cc=auto` then no prompt will be shown and inferred mailing
> lists will be used.
> 
> Additionally, the selected mailing lists will also be shown in the users
> `$EDITOR` when the user writes the pull request message. For example:
> 
>   
>   
>   
>   
>   
>   
>   
>   
>   
>   
>   
>   
>   
>   
>   
> 
> As with all flags to Skara's CLI commands, a default value can be configured for
> the `--cc` flag. This means that users that so wish can opt in to always use the
> inferred mailing lists by running:
> 
> $ git config --global pr.create.cc auto
> 
> Testing:
> - [x] Manual testing on Linux x64
> 
> Thanks,
> Erik

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

  Fix tests

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

Changes:
  - all: https://git.openjdk.java.net/skara/pull/750/files
  - new: https://git.openjdk.java.net/skara/pull/750/files/f88fd379..59e2cfbb

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=skara&pr=750&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=skara&pr=750&range=00-01

  Stats: 4 lines in 2 files changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/skara/pull/750.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/750/head:pull/750

PR: https://git.openjdk.java.net/skara/pull/750