roundwork 0.0.1

• Initial CRAN submission.
• This new package is a spin-off from scrutiny. Much of the code was copied from there; see Github issue lhdjung/scrutiny#68.
• Notable changes compared to scrutiny:
  • unround() no longer guesses whether the bounds are inclusive with rounding = "even". This is highly variable in the underlying base::round() function, and the firm statement in earlier versions of scrutiny that the bounds are never inclusive was unwarranted.
  • unround(), anti_trunc() , and round_anti_trunc() now correctly return zero in a rare edge case (rounding or unrounding zero while assuming "anti_trunc" rounding).
  • Five new functions around round_ties_to_even() implement the IEEE 754 rounding standard by wrapping existing functions.