[SPARK-2924] remove default args to overloaded methods

Not supported in Scala 2.11. Split them into separate methods instead.

Author: Anand Avati <avati@redhat.com>

Closes #1704 from avati/SPARK-1812-default-args and squashes the following commits:

3e3924a [Anand Avati] SPARK-1812: Add Mima excludes for the broken ABI
901dfc7 [Anand Avati] SPARK-1812: core - Fix overloaded methods with default arguments
07f00af [Anand Avati] SPARK-1812: streaming - Fix overloaded methods with default arguments
(cherry picked from commit 7589c39d39a8d0744fb689e5752ee8e0108a81eb)

Signed-off-by: Patrick Wendell <pwendell@gmail.com>
Revert "[SPARK-2468] Netty based block server / client module"

This reverts commit 3f23d2a38c3b6559902bc2ab6975ff6b0bec875e.