Log message:
math: Replace RMD160 checksums with BLAKE2s checksums

All checksums have been double-checked against existing RMD160 and
SHA512 hashes

Log message:
math: Remove SHA1 hashes for distfiles

Log message:
(math/R-prettyunits) Updated 1.0.2 to 1.1.1

# 1.1.1

* Fix spurious zero fractions in `pretty_bytes()` when formatting
  vectors of sizes (#23).

# 1.1.0

* `pretty_dt()`, `pretty_ms()` and `pretty_sec()` now handle `NA` values
  properly, and return `NA_character_` for them (#10, @petermeissner).

* `pretty_bytes()` now formats quantities just below the units better.
  E.g. 1MB - 1B is formatted as `"1 MB"` instead of `""1000 \ 
kB"` (#18).

* `pretty_bytes()` now has multiple styles. In particular, a fixed width
  style is useful for progress bars. Another style avoids the left-padding
  with spaces.

* The new low level `compute_bytes()` function can be used to create
  custom formatters for bytes.

Log message:
Update all R packages to canonical form.

The canonical form [1] of an R package Makefile includes the
following:

- The first stanza includes R_PKGNAME, R_PKGVER, PKGREVISION (as
  needed), and CATEGORIES.

- HOMEPAGE is not present but defined in math/R/Makefile.extension to
  refer to the CRAN web page describing the package.  Other relevant
  web pages are often linked from there via the URL field.

This updates all current R packages to this form, which will make
regular updates _much_ easier, especially using pkgtools/R2pkg.

[1] http://mail-index.netbsd.org/tech-pkg/2019/08/02/msg021711.html

Log message:
R-prettyunits: update to canonical form of an R package.

Log message:
math/R-prettyunits: Import version 1.0.2

Pretty, human readable formatting of quantities. Time intervals:
1337000 -> 15d 11h 23m 20s. Vague time intervals: 2674000 -> about a
month ago. Bytes: 1337 -> 1.34 kB.