Clarify license/copyright of logo

The license in https://github.com/common-workflow-language/logo/blob/master/LICENSE.md says

> The Common Workflow Language Logos are (C) Copyright 2016 the Common Workflow Language Project and are released under the terms of the GNU Lesser General Public License, version 3 or any later version, or, at your option, of the Creative Commons Attribution-ShareAlike 3.0 Unported License.

Yet the license of the (smaller) logo at https://github.com/common-workflow-language/common-workflow-language/blob/master/site/CWL-Logo-Header.png is (now) [distributed under Apache license 2.0](https://github.com/common-workflow-language/common-workflow-language/blob/master/LICENSE.txt)

Is this license mismatch intentional because of the resolution differences or just historic? I assume the actual right holder has independently re-contributed the logo to the Apache licensed PNG.

As far as I know, _Common Workflow Language Project_ is not a legal entity and can't own copyright. So presumably the original contributor of the logo (or their employer) would own the rights. Can this be clarified who are the copyright holders and attribution of the logo?

This affects: apache/incubator-taverna-common-activities#20 which wants to use the low-res PNG.