Correct examples using suggests packages to run conditionally

[nehill197]

Conditionally run examples that depend on packages in suggests for sn package.

[nehill197]

No suggests action is passing now!
I had to add this to the beta-binomial vignette code chunks:
{r eval = requireNamespace("tidyr", "ggplot2", "scales"), .....}

and this to the remaining example that used a suggested package

@examplesIf requireNamespace("hms")
# run example here

[aylapear]

Looks good to me, as long as all the actions are passing then it sounds good. I would suggest running it through the win builder system just to be certain all systems are passing.