ISPN-3489 The REST Cache store now uses HttpComponents 4.x instead of httpclient 3.x
ISPN-3517 Infinispan server ignores persistence configuration
ISPN-3510 Infinispan 6.0 should be able to parse 5.2.x config files and use 5.2.x custom cache storesi

* the server can now read 5.2.x configurations
* removed 5.3.x configuratins
ISPN-3510 Infinispan 6.0 should be able to parse 5.2.x config files and use 5.2.x custom cache

* updated as per the review comments