R updates:
  * cache nrows, colnames, ncols, and any_enum values into the H2OParsedData object
  * fix a few old tests
  * have a unified way of getting and updating H2OParsedData objecsts
Merge branch 'master' of https://github.com/0xdata/h2o

Conflicts:
	R/h2o-package/R/Classes.R