LLAP move RowGroup reading to StrippePlanner

LlapDataREader is almost identical to ORC's DataREader, however the main issue the readFileData method of the latter takes a DiskRangeList instead of a BufferChunkList.

ORC-1.6 uses a separate StripePlanner that reads RowGroups converting them to BufferChunks while in LLAP we are doing our own custom planning with DiskRanges.

I am opening this ticket to explore moving LLAP to Stripe planning