TEZ-1701. ATS fixes to flush all history events and also using batching. (hitesh)

(cherry picked from commit a6c8006c37334099a8a77befa3b687113514a35c)
TEZ-1716. Additional ATS data for UI. (hitesh)

(cherry picked from commit ede0e645a9f4fdda44842a46b7fcf9edecdf50b2)
TEZ-1722. DAG should be related to Application Id in ATS data. (hitesh)

(cherry picked from commit c570a0e12921fff5787877ceb5612b08115d77a4)
TEZ-1711. Don't cache outputSpecList in VertexImpl.getOutputSpecList(taskIndex). (zjffdu)

(cherry picked from commit 7f8fc7530b39106e238c67b7bd22d5ed5670d449)
TEZ-1703. Exception handling for InputInitializer. (zjffdu)

(cherry picked from commit 4ec29425d63decfd8de4e1528f043271cf7cb3b2)
TEZ-1698. Cut down on ResourceCalculatorProcessTree overheads in Tez (Rajesh Balamohan & Gopal via Rajesh Balamohan)
(Cherry-picked from 4d94652c817d83204ae06d618ade07f15fbed8d7)
TEZ-1703. addendum - fix flaky test. (zjffdu)

(cherry picked from commit 8f8a81f7a17f9018ae4e87bf0fca9d6cdc0a5ba4)
TEZ-1698. addendum - fix license template issue. (Rajesh Balamohan)
(Cherry picked from commit 81322efc2b8b843008cb3bebe8e5db78af20eb58)
TEZ-1725. Fix nanosecond to millis conversion in TezMxBeanResourceCalculator  (Rajesh Balamohan)
(Cherry picked from commit b66ff72cc02d333d36c312562b7f06ac174e9830)
TEZ-1726. Build broken against Hadoop-2.6.0 due to change in NodeReport. (sseth)
(cherry picked from commit b768c0f19be158ce05c62bcc9455b75c92ac8831)