Automatically generate downloads page for each release

[sbesson]

With the upcoming migration of the documentation to sphinx, the only remaining pages to be systematically updated at each release should be the downloads and the front pages.

We should explore ways to automatically generate the downloads pages since most of its content can be parsed from cvs.openmicroscopy.org.uk.

[jmoore]

Starting work here, jmoore@necromancer /var/www/cvs.openmicroscopy.org.uk/snapshots/omero $ vi gen.py

[jmoore]

I'm considering this done. Sebastien, can you review the git under /var/www/cvs.openmicroscopy.org.uk/snapshots/omero and see what you think. You can test with:

./gen.py 4.4.3 b5

[sbesson]

Tested with 4.4.2 & 4.4.3 snapshots.

Token substitution works so well I realized some MD5 checksums were wrong on the current Downloads page.

Other links in the tmpl.txt will need to be replaced (e.g. developers documentation). We may want to bring this script + page template into git eventually.

[jmoore]

Added calculation of sha1 from tag name and fixed URLs. Up for another look, Sebastien?

[sbesson]

Retested with

./gen.py 4.4.3 b5

Resulting page is available at ​https://www.openmicroscopy.org/site/support/omero4/copy_of_downloads and is looking good.
Additional doc links will need to be redirected for 4.4.4 but manual intervention will be required anyways (e.g. the announcement post).