Log Message:
(math/R-tibble)  Updated 3.1.2 to 3.1.4

# tibble 3.1.4

## Features

- `as.data.frame.tbl_df()` strips inner column names (#837).
- `new_tibble()` allows omitting the `nrow` argument again (#781).

## Documentation

- Move `vignette("digits")`, `vignette("numbers")`, `?num` \ 
and `?char`
  from the pillar package here (#913).
- Replace `iris` by `trees` (#943).
- Various documentation improvements.
- New `?tibble_options` help page (#912).

## Performance

- `x[i, j] <- one_row_value` avoids explicit recycling of the
  right-hand side, the recycling happens implicitly in
  `vctrs::vec_assign()` for performance (#922).

## Internal

- Vignettes are now tested with a snapshot test (#919).
- `new_tibble()` uses `vctrs::new_data_frame()` internally (#726,
  @DavisVaughan).
- Adapt to pillar 1.6.2.
- Fix tests for compatibility with pillar 1.6.2.

# tibble 3.1.3

## Bug fixes

- `tbl[row, col] <- rhs` treats an all-`NA` logical vector as a
  missing value both for existing data (#773) and for the right-hand
  side value (#868). This means that a column initialized with `NA`
  (of type `logical`) will change its type when a row is updated to a
  value of a different type.
- `[[<-()` supports symbols (#893).

## Features

- `as_tibble_row()` supports arbitrary vectors (#797).
- `enframe()` and `deframe()` support arbitrary vectors (#730).
- `tibble()` and `tibble_row()` ignore all columns that evaluate to
  `NULL`, not only those where a verbatim `NULL` is passed (#895,
  #900).
- `new_tibble()` is now faster (#901, @mgirlich).

## Internal

- Establish compatibility with rlang > 0.4.11 (#908).
- Use `pillar::dim_desc()` (#859).
- Establish compatibility with testthat > 3.0.3 (#896, @lionel-).
- Bump required versions of ellipsis and vctrs to avoid warning during
  package load.