Support creating release notes to a file on disk

[AdmiringWorm]

Detailed Description

it would be helpful to be able to create release notes to a specific file on you local system, instead of having to create it remotely on GitHub/GitLab.

Context

When creating a release on GitLab it is creating a tag at the same time, this can be undesirable when the intention is to draft a release note and have a look over it without wanting to do a release immediately, or if there is a need to wait on something but still want to have the release notes reviewed.

Possible Implementation

Add a new argument to the create option that accepts an output path, this can then be used to override the handler that creates releases.

Your Environment

• Version Used: 0.18.0
• Edition Used (.NET Core, .NET Framework): .NET Core
• Operating System and version (Windows 10, Ubuntu 18.04): Windows