feat: multiline exclusion regexes (fix #996) (#1807)

* Support excluding multiline regexes, O(N) algorithm by nedbat.

* Fix test_parser.py.

* Actually fix tests and mypy check.

* Format multiline exclusion tests.

* Apply suggestions from code review by @nedbat.

Co-authored-by: Ned Batchelder <ned@nedbatchelder.com>

* Improve and add new tests to test_parser.py.

* Skip test_multiline_exclusion_block2 if Python version < 3.10.

* Add tests for exclusion of a whole module or from a marker until the end of the file.

* tweak the regexes in the tests

* test: add one more test for the specific #996 use

* docs: explain multi-line exclusion regexes

* build: the next version will be 7.6.0

* better: no whitespace in regexes

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Co-authored-by: Ned Batchelder <ned@nedbatchelder.com>
5 files changed