ISPN-3772 Reduce marshalling payload sizes

* Unless compatibility and query mode are enabled, do not use
Flag.OPERATION_x.
* Flags, which are shipped in EnumSet instances, are now marshalled
using Externalizers, leading to a reduction in size as a result of
not writing class information.
* Except for primitive types, arrays can be shrinked by using
exterternalizers for those arrays more commonly shiped. This results
in array type information not being written to the payload.
* Add Arrays$ArrayList to the types covered by the ListExternalizer,
which it now covers for all list implementations.

Flags also used in query
Ignore Checkstyle metadata produced by the Eclipse plugins
ISPN-3799 Update base CHMv8 to rev 1.120

* It primarily fixes and edge case where CHM.get will sometimes fail to
find a key present in the map.
ISPN-3839 Compatibility Mode tests didn't shutdown all the cache managers
ISPN-3841 L1NonTxInterceptor - Invalid format of log.tracef message
'Release Script: update versions for 6.0.2-SNAPSHOT'
ISPN-3731 Multicast messages can be replayed to new node

Keep track of the first cache topology was a member, and ignore commands
with a lower topology id.
Change version to 7.0.0-SNAPSHOT