Upgrade docs

[llrs-roche]

Fixes #16

• Updates the dictionary
• Uses the latest roxygen2 (which adds contributors and other minor changes)
• Fixes some issues with the documentation missing values and examples.

I am not sure what to do with these methods:

! Missing `\value` section in 3 files:
• man/knitr_logger_styles.Rd
• man/knitr_mutable_header.Rd
• man/knit_print.knitr_log.Rd
! Missing `\examples` section in 3 files:
• man/knitr_logger_styles.Rd
• man/knitr_mutable_header.Rd
• man/knit_print.knitr_log.Rd

I think they shouldn't have a help page as they are "internal" we can keep the comments but I would not generate a .Rd file for them.