small fix for href attribute on View on site
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
promote Ipipan to a Managing Node and improve the HTML/CSS structure

It should now be easier to add/move nodes. Furthermore, the semantics of
the HTML is more correct (replaced tables with lists).
Merge pull request #733 from cspurk/master

promote Ipipan to a Managing Node and improve the HTML/CSS structure
correct case of IPIPAN
Merge pull request #734 from cspurk/master

correct case of IPIPAN Managing Node
Merge branch 'master' of https://github.com/JuliBakagianni/META-SHARE
add BME-TMIT and FFZG nodes
add/rm
add/rm
add/rm
add/rm
add/rm
add/rm
Better quality logos for CESAR nodes.
Renamed some logo's filenames.
cleanup server statistics page; remove unused .js and .css files; fix the sortable table; add new columns
fix problem with usage statistics updating when there are no longer available resources after syncronization
fix error with X-Forwarded-For headers with multiple IP addresses

We have to make sure here that the `_get_ipaddress` function returns at
most one IP address.