1.2.2

fix: the tests were not passing anymore

Due to recent deep-but-small changes, some tests were not passing anymore.
This commit fixes what is important to fix, the test battery is not fully passing but the cases with known issues are minor issues.

Implementation details: this fix mainly concerns `\n`-related issues at the backend level.

modified:   omd_backend.ml
modified:   omd_parser.ml