Preview release 2.0.0 M2

This release includes all patches from 1.6.1:

1.6.1

• Disallow TimeUUID Predicate Pushdown (SPARKC-405)
• Avoid overflow on SplitSizeInMB param (SPARKC-413)
• Fix conversion of LocalDate to Joda LocalDate (SPARKC-391)
• Shade Guava to avoid conflict with outdated Guava in Spark (SPARKC-355)