Adds `[repository].DOWNLOAD_OR_CLONE_METHODS` (defaulting to
"download-zip,download-targz,download-bundle,vscode-clone"), which lets
an instance administrator override the additional clone methods
displayed on the repository home view.
This is purely display-only, the clone methods not listed here are still
available, unless disabled elsewhere. They're just not displayed.
Fixes#710.
Signed-off-by: Gergely Nagy <forgejo@gergo.csillger.hu>
(cherry picked from commit 2aadcf4946)
(cherry picked from commit 42ac34fbf9)