vctrs 0.3.7

• vec_ptype_abbr() gains arguments to control whether to indicate
  named vectors with a prefix (prefix_named) and indicate shaped
  vectors with a suffix (suffix_shape) (#781, @krlmlr).

• vec_ptype() is now an optional performance generic. It is not necessary
  to implement, but if your class has a static prototype, you might consider
  implementing a custom vec_ptype() method that returns a constant to
  improve performance in some cases (such as common type imputation).

• New vec_detect_complete(), inspired by stats::complete.cases(). For most
  vectors, this is identical to !vec_equal_na(). For data frames and
  matrices, this detects rows that only contain non-missing values.

• vec_order() can now order complex vectors (#1330).

• Removed dependency on digest in favor of rlang::hash().

• Fixed an issue where vctrs_rcrd objects were not being proxied correctly
  when used as a data frame column (#1318).

• register_s3() is now licensed with the "unlicense" which makes it very
  clear that it's fine to copy and paste into your own package
  (@maxheld83, #1254).