Better quality logos for CESAR nodes.
make sure to never throw any `UnboundLocalError`s in the `finally` block
Merge pull request #728 from dmavroeidis/master

Better quality logos for CESAR nodes
Merge branch 'master' of https://github.com/ioannagian/META-SHARE into various-improvements
various smaller menu improvements
Merge pull request #729 from cspurk/various-improvements

various improvements – see individual commits
Renamed some logo's filenames.
Merge github.com:metashare/META-SHARE
Removed incorrect logos.
Merge pull request #730 from dmavroeidis/master

Corrected logos' filenames
fix: remove all existing `SessionResourcesTracker`s when repairing

We have to remove all existing `SessionResourcesTracker`s when repairing
the recommendation structures as these trackers store resource objects
that might not exist anymore.
Merge pull request #731 from cspurk/master

fixed/improved recommendations repair code
added metadata user manual
css improvements in metadata info page
added metadata schema information
added menu item for metadata schema info