WIP: [OS-8158] Update proxy config, purge cache/config only on ControllerUnpublishVolume, change VolID to Repository name/tag

Temporary quick fix applied on our clusters: !7 (closed)

This MR fixes:

• Purging CVMFS cache on container create/delete. Purging will happen only on PVC creation/deletion through driver-requires-attachment=true
• Update PROXY Config
• Sharing of the cache between all pods and users in the cluster (CVMFS is read-only shared filesystem)

TODO:

• Assign Volume ID according to repository and tag/hash to avoid cache duplication, corresponding caches will look as below while specifying tag or while specifying hash

$ ls /var/cache/cvmfs/
csi-csi-cvmfs-cms.cern.ch-abcdef  csi-csi-cvmfs-cms.cern.ch-trunk

• Move logic of config/purge from NodeServer to ControllerServer
• Investigaste CSI Attacher not calling ControllerPublishVolume/ControllerUnpublishVolume

@pkothuri