donkey 1.17.3 — one answer to each question, and f leaves folded text alone

A bug fix release. The code was gone over for functions that answer
the same question with code of their own, and four such pairs had
drifted apart into bugs: Split's own copy of the wrap's pair lookup,
three ways of working out a V selection's lines, the cursors'
character count, and the first idle moment re-reading one option of
three. Each question now has one function, and donkey.el is 175
lines smaller for it. Folded text is now never changed by f.

Fixed -- you will notice these

• V J d, V J y, M-w and C-u 2 V d over a selection ending on
  an empty line left that line behind: on "a", an empty line and "b",
  V J d killed "a" and its newline only. The empty line is taken now.
• x, d, y and c at the cursors on an accented letter written
  with a combining mark, or an emoji made of joined ones, took one code
  point and left the rest at every cursor. They take the character
  whole, as one cursor has since 1.17.2.
• In a split, a delimiter beside an escaped quote took the escaped
  quote off: f " on a \"foo" b left a \foo b. A split now wraps
  exactly as a wrap key does, junk rows in the pair table included.
• A pair, or a refused command, added with add-to-list in your init
  file took effect only after M-x donkey-pair-refresh or
  M-x donkey-refresh-suppressed-commands; the first idle moment
  re-read only the wrap keys. It reads every option now.
• RET with an Enter rule whose command is a lambda signaled
  wrong-type-argument; it runs the lambda now.

Changed -- you will notice these

• f leaves out matches inside a fold whatever search-invisible
  says. With search-invisible set to t it used to hold them and
  write into the fold. Folded text is changed by r r and r q; with
  r q, unfold first, so you can see each match you answer.
• C-u -1 m s marks the sentence before point, as C-u -1 m w marks
  the word before it; it used to mark the sentence at point. With
  nothing before, it refuses and leaves point and the mark alone.

Fixed

• m i and m a logged "Mark set" before saying what they selected.
• m i with a pair-table row whose closing half is not a character
  raised a raw error; it says the delimiter is unsupported.
• Undoing a split did not count what it recorded against undo-limit,
  so a large split kept two full undo entries -- some 13 MB each at
  850,000 places. The newer is now cut to the limit like any other.

Under the hood

• One function now answers each of: which pair a delimiter belongs to,
  which kind of buffer this is, which cursor a state asks for, whether
  a mode is on a list, which lines a V selection covers, how a split
  deletes at every place, how its state is cleared, and how y and
  d choose what to act on. The Org agenda's own Enter handler is
  gone: the agenda's RET has been the agenda's own since 1.12.0.

Upgrading

Nothing to do. If you set search-invisible to t so that f would
reach into folds, use r r or r q there instead.