Update readme to include 4 byte length in rle columns
Clarify based on comments
Revert "Clarify based on comments"

This reverts commit 190cef8db5f5fa4d366569fc8066e2f350d69538.
fix whitespace
fix typo
Merge pull request #46 from Parquet/alexlevenson/update-readme-rle-4bytes

Update readme to include 4 byte length in rle columns