This is a purely cosmetical change, to consistently prefer one of
two (both acceptable) choises for the word parsable in documentation and
code. I don't really care which to use, but acording to wiktionary
https://en.wiktionary.org/wiki/parsable#English parsable is preferred.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#4682