Request for support for issues closed with keywords in non-master branch.

Reference:
[GitHub: Closing issues using keywords](https://help.github.com/articles/closing-issues-using-keywords/)

If you use one of GitHub's keywords for closing an issue in a branch then the issue is marked for closing when the branch is merged with `master`.

*Note: I'm using `git flow`.*
So if i'm working in `hotfix/1.0.6` based on `master`.
And commit with the message `Resolved #12 ....` and push it.
Then the issue is marked for closing when the branch is merge into `master`.
When i finish the branch with `git flow hotfix finish 1.0.6` it tags the last commit with `1.0.6` and merges it into `master`.
When i then run `gren r` I don't get `#12` in my release notes.
In fact since I'm always doing this all my release notes end up on the next tag instead...

Seems to me like this is an issue of `<` instead of `<=`.

Start by reproducing the report with `git flow hotfix finish 1.0.6`, a commit containing `Resolved #12`, and `gren r`. Inspect how `gren r` selects issues between the previous and current tags, then verify that an issue closed when the branch merges into `master` appears in the release notes for the correct tag.

Written by the indexing model from the issue text.