Create new milestones after releasing

[alcaeus]

After a release is tagged, the new tool should create new milestone(s) for future releases. Consider the following scenarios:

Feature: New milestones

  Scenario: When tagging a new patch release, the tool should create a milestone for the subsequent patch release
    Given following existing branches:
      | name  |
      | 1.0.x |
    Given following open milestones:
      | name  |
      | 1.0.3 |
    When I close milestone "1.0.3"
    The milestone "1.0.4" should have been created

  Scenario: When tagging a new minor release, the tool should create milestones for the subsequent patch and minor releases
    Given following existing branches:
      | name  |
      | master |
    Given following open milestones:
      | name  |
      | 1.1.0 |
    When I close milestone "1.1.0"
    The milestone "1.1.1" should have been created
    And the milestone "1.2.0" should have been created

  Scenario: When tagging a new major release, the tool should create milestones for the subsequent releases
    Given following existing branches:
      | name  |
      | master |
    Given following open milestones:
      | name  |
      | 2.0.0 |
    When I close milestone "2.0.0"
    The milestone "2.0.1" should have been created
    And the milestone "2.1.0" should have been created
    And the milestone "3.0.0" should have been created

For pre-releases (see #25), the following feature comes to mind: further features should be implemented depending on the scope of pre-release support.

  Scenario: When tagging a new alpha release, the tool should only create a milestone for the subsequent alpha and for the stable release
    Given following existing branches:
      | name  |
      | master |
    Given following open milestones:
      | name  |
      | 1.0.0-alpha1 |
    When I close milestone "1.0.0-alpha1"
    The milestone "1.0.0-alpha2" should have been created
    And the milestone "1.0.0" should have been created

[Ocramius]

Moved to laminas/automatic-releases#26