Fix some issues reported by lintian

Fix some issues reported by lintian

• Trim trailing whitespace.
• Use secure copyright file specification URI.
• Drop no longer supported add-log-mailing-address setting from debian/changelog.
• Use secure URI in debian/watch.
• Update standards version to 4.4.1, no changes needed.
• Rely on pre-initialized dpkg-architecture variables.
• Fix day-of-week for changelog entries 1.3.11-1.

This merge proposal was created automatically by the Janitor bot (https://janitor.debian.net/lintian-fixes).

You can follow up to this merge proposal as you normally would.

Build and test logs for this branch can be found at https://janitor.debian.net/lintian-fixes/pkg/calcoo/babc4e4f-720b-4026-aa77-4b8792096ca1.