Merge branch 'es/chain-lint-more'

Improve built-in facility to catch broken &&-chain in the tests. * es/chain-lint-more: chainlint: add test of pathological case which triggered false positive chainlint: recognize multi-line quoted strings more robustly chainlint: let here-doc and multi-line string commence on same line chainlint: recognize multi-line $(...) when command cuddled with "$(" chainlint: match 'quoted' here-doc tags chainlint: match arbitrary here-docs tags rather than hard-coded names