Cache size

[jburel]

Fix problem described in http://trac.openmicroscopy.org.uk/ome/ticket/10502

To test:

• Connect, open an image
• Switch user.
• Open the image.
• Check the insight log and make sure you do not have the following entry

Cannot retrieve cache with ID: -1java.lang.IllegalStateException: The CacheManager is not alive.
    at net.sf.ehcache.CacheManager.checkStatus(CacheManager.java:831)
    at net.sf.ehcache.CacheManager.getCache(CacheManager.java:506)
    at org.openmicroscopy.shoola.env.cache.CacheServiceImpl.setCacheEntries(CacheServiceImpl.java:263)

[scottlittlewood]

@jburel Tested as described above. No cache error seen in the log.

Tested using image owned by user-10 and viewed by user-4 in read-write-1 group on howe.

Ready to merge.

[jburel]

Thanks. Merging