Typo in vignette

[llrs]

There is a v before the quote of the version that prevent it from being correctly evaluated:

https://github.com/al2na/methylKit/blob/0a5581c33accb8493f00658325fc1d8c4a6370c8/vignettes/methylKit.Rmd#L2

It should be

title: "methylKit: User Guide r packageVersion('methylKit')"

This is present in both 3.18 and devel branch.