Update to Tibble Package

[SHogenboom]

I receive the following warning indicating that the package is out of date:

Warning message:
`as_data_frame()` was deprecated in tibble 2.0.0.
Please use `as_tibble()` instead.
The signature and semantics have changed, see `?as_tibble`.

Everything appears to work, but a simple update should resolve the warning?

[SHogenboom]

Uppon inspection of the code this was already resolved, but the current version on CRAN still has this issue.

Resolved by downloading directly from the github respository.