Release Arguable version 13.0.0-alpha.7.
Release Arguable version 13.0.0-alpha.7.

 * Upgrade `interrupt` to `11.0.0-alpha.26`.
 * Upgrade `rescue` to `7.0.0-alpha.19`.
 * Fix `LICENSE` goof.
 * Upate `LICENSE` for current year.

Closes #323.

bigeasy/arguable