[geotools/geotools] 5c6cef: update osgeo projects logo (#1819)

[Jody Garnett]

Branch: refs/heads/19.x
Home: https://github.com/geotools/geotools
Commit: 5c6cef8ed38120dd7d58baaf91e3c1f9438f4538
https://github.com/geotools/geotools/commit/5c6cef8ed38120dd7d58baaf91e3c1f9438f4538
Author: Jody Garnett <jody.g...@gmail.com>
Date: 2018-03-06 (Tue, 06 Mar 2018)

Changed paths:
M docs/themes/geotools-tutorial/static/geotools-tutorial.css
A docs/themes/geotools-tutorial/static/img/OSGeo_project.png
R docs/themes/geotools-tutorial/static/img/osgeo-logo.png
M docs/themes/geotools-web/static/geotools-web.css
A docs/themes/geotools-web/static/img/OSGeo_project.png
R docs/themes/geotools-web/static/img/osgeo-logo.png
M docs/themes/geotools/static/geotools.css
A docs/themes/geotools/static/img/OSGeo_project.png
R docs/themes/geotools/static/img/osgeo-logo.png

Log Message:
-----------
update osgeo projects logo (#1819)

* update osgeo projects logo

* revise based on feedback