More test fixes

- Remove testPurgedBody
  This has been disabled for quite some time and is no longer applicable
  with the new buffer system.

- move testFlags to t_get.cc
  This is a simple test and does not belong in the special "t_mock.cc"
  tests

- Move testIssue59 to t_regression.cc

- iotests: Use EIFNET rather than explicit error code
  libuv does not return 'NETWORK_ERROR' or 'CONNECT_ERROR' but rather
  'UNKNOWN_HOST'

- t_mock: add some logging

- mc/t_alloc.cc - cast nb_IOV/lcb_IOV

- mctest.h - don't free pipelines individually

Change-Id: I41952d82871bead27d55908fd5c7e9f5e3f2f41a
Reviewed-on: http://review.couchbase.org/36125
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>