contentvalidR 0.10.1

A documentation release. The README now documents the handoff to nomologR in
its own section, matching the one the nomologR README carries for the
handoff from contentvalidR, so either front page explains how the two
packages connect. Released on GitHub and R-universe; CRAN keeps 0.4.0 until the joint
1.0.

No computed value changes. Across 25 analyses spanning every workflow,
every value 0.10.0 returns is identical in 0.10.1, and no function, argument,
or handoff field changed.

• The README has a section on the handoff to nomologR, just above the
  references: what a handoff carries, the two nomologR calls that read it, how
  to read its decisions, and how the schema is versioned. The nomologR README
  carries the mirror section, so the handoff can be found from either
  package's front page.
• Krippendorff (2011) now links to the copy on the Annenberg School's site,
  because the Penn repository copy had become unreliable to reach: it
  answered in 2 to 10 seconds, returned a server error, and timed out. It is
  the same paper, dated 2011.1.25, with its reading list updated in 2013. The
  expert-panel vignette's reference list now gives the link too.
• The reader in nomologR is now tested against handoffs from contentvalidR
  0.6.0 through 0.10.0, and the README says so.