This changes the FetchRelease implementation to look up draft releases directly using by its pending tag name, as opposed to resorting to the Releases list API which is backed by Elastic Search and thus suffers replication lag after the creation of a draft release.
Bonus: all release lookup functions now accept a context for cancellation.
Output flag allows one to download to a specific file location or event redirect to output using '-' as argument.
Co-authored-by: Mislav Marohnić <mislav@github.com>
The `zipball_url` and `tarball_url` fields on the Release API payload
always link to "legacy" archives that are of a different format than
those one would get if they downloaded an archive from a Release using
the web interface. The GitHub API does not seem to publish links to
non-legacy archives.
This adds a redirect hack to turn "legacy" Codeload URLs into non-legacy
ones with the goal of ensuring the consistency of user experience when
downloading archives.
