ChangeScreen2: Show download commands defined by plugins

The download commands are returned as part of the FetchInfo of a
revision, but only if the download commands are requested by setting
the option DOWNLOAD_COMMANDS.

This allows to completely customize the download commands on a Gerrit
installation.

This change only effects the download commands that are shown on
ChangeScreen2.

For non-anonymous download commands the username is now again included
into the displayed download commands. Also the HTTP scheme and the
Anonymous HTTP scheme can be used at the same time.

With this change the patch download (base64 & zipped) is still
hard-coded in Gerrit core and does not come from a plugin.

Bug: issue 2116
Change-Id: I8fb21fdeb1a98548ce9027655e1b5e467ee2d27e
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
11 files changed