ISPN-4311 Do not try to be clever with file separators on Windows, just replace any backslashes with slashes
ISPN-4467 Fix BulkUtil formatting
ISPN-4467 Bulk get keys should use a compatibility collator

* Use a different collator when compatibility is enabled which makes
the necessary transformations from POJO to byte arrays.
ISPN-1951 Use MERGE3 in the default UDP configuration

TEST_PING needed some changes, as MERGE3 doesn't trigger Discovery.findMembers()
Smaller timer pool and queue.
Still causes lots of failures.