bug: CRAN version `0.2.2` doesnt align with `NEWS.md`

[jjjermiah]

according to the NEWS.md:

S7/NEWS.md

Lines 29 to 33 in e7cc230

	# S7 0.2.2
	* `validate()` now signals validation errors with class
	`S7_error_validation_failed`, so they can be caught with `tryCatch()`
	(#602, #605).

the error types introduced in #605 should be in 0.2.2, but the version on CRAN and the github Release for 0.2.2 dont have the feature (R/valid.R@L86-L90)

S7/R/valid.R

Lines 86 to 90 in e7cc230

	stop(errorCondition(
	msg,
	call = NULL,
	class = "S7_error_validation_failed"
	))

[hadley]

I must have accidentally merged a couple of PRs before fully completing the release process. Here's the actual 0.2.2 news: https://github.com/cran/S7/blob/master/NEWS.md