Updates for mem tracking.

Change-Id: I7a31b31383c18f5561e0c495ea87a43d3c52a782
Update Close() to return void.

Change-Id: Ia81259128dc24ab02e02a60b5ea3c5620ad4b60b
IMPALA-466: Updates to errno handling.

Change-Id: I475b75860cf01b0180134f9092cec4ab23082be3
Allow UDFs in conjunct expressions.

Change-Id: Ie205c8cd6b35117311f0aab58b9170109c07082f