Add documentation for Infinispan 6.0
Update docs to reflect cache stores having moved out
Update docs to reflect more hot rod clients
ISPN-3051 Allow configuring the number of segments per node

Because the algorithm for allocating segments changed, some tests had to
change as well. E.g. we can't always find a MagicKey that will be owned
by 3 particular members, as in StateResponseOrderingTest.
ISPN-3172 Define and manage indexes and schemas via JMX

Refactored all protobuf serialization context stuff, properly injected it into the field bridge, added a MBean for it so new proto files can be registered. The protobuf metadata is kept in a replicated cache.

Also fixes ISPN-3523, by lifting the marshalling and query construction limitations that made it imposible for remote query to interoperate with embedded query.