* Support map type in orc extension.
Added getMapObject in OrcHadoopInputRowParser
Updated parse tests to parse map-type field in OrcHadoopInputRowParserTest
* changed from for-loop to foreach
* added resolution of column names when map types are exploded to several
columns. updated the document as well -- orc.md.
* Update orc.md
change from review
* InputRowParser to decode OrcStruct from OrcNewInputFormat
* add unit test for orc hadoop indexing
* update docs and fix test code bug
* doc updated
* resove maven dependency conflict
* remove unused imports
* fix returning array type from Object[] to correct primitive array type
* fix to support getDimension() of MapBasedRow : changing return type of orc list from array to list
* rebase and updated based on comments
* updated based on comments
* on reflecting review comments
* fix bug in typeStringFromParseSpec() and add unit test
* add license header
Dan Suzuki
Fangjin Yang
Keuntae Park