Release 6.20.0: Extended life time of cached objects for the database pool and filestore

[changerequest]

The OX system dies under heavy load because to much simultaneous locks are created in the underlying MySQL database. These locks should be avoided with caching as much as possible.

The cache.ccf of groupware and administration daemon gets 4 modified values as shown below:

jcs.region.Filestore.cacheattributes.MaxMemoryIdle TimeSeconds=360
jcs.region.Filestore.elementattributes.MaxLifeSeco nds=-1
jcs.region.Filestore.elementattributes.IdleTime=36 0
jcs.region.OXDBPoolCache.cacheattributes.MaxMemory IdleTimeSeconds=360
jcs.region.OXDBPoolCache.elementattributes.MaxLife Seconds=-1
jcs.region.OXDBPoolCache.elementattributes.IdleTim e=360

This keeps the cached objects for longer times in the cache.