mercurial: remove head support

Closes #26822.
mercurial: vendor docutils

Install docs without requiring a global docutils
nload: fails with clang

Closes #27823.
Remove iulib

Closes #27238.
add helpers for testing command output
use test helpers
mercurial: add 3.0 bottle.
ansifilter: add 1.7 bottle.
align: add 1.7.2 bottle.
lorem: add 0.6.1 bottle.
calc: add 2.12.4.8 bottle.
algol68g: add 2.8 bottle.
z80dasm: add 1.1.3 bottle.
aardvark_shell_utils: add 1.0 bottle.
jsmin: add 2013-03-29 bottle.
csv-fix: add 1.6 bottle.
multimarkdown: add 4.5 bottle.
jsonpp: add 1.2.0 bottle.
jq: add 1.3 bottle.
csvprintf: add 1.0.3 bottle.