Although `yes` and `no` are recognized as booleans by the pyyaml parser,
the correct keywords are `true` and `false` (as highlighted by the newly
added `truthy` rule).
This commit replaces the use of `yes`/`no` by `true`/`false` and
advertise it in the docs, but also makes sure this change is
backward-compatible (so that `yes` and `no` still work).
This commit extracts the inline mappings logic defined in the previous
commit to a separate config option, as suggested by @adrienverge. I'll
squash this into the previous commit if the change is accepted. (I named
the option slightly differently to what was suggested as I think my
proposal reads better without consulting the docs: I'd be happy to
reconsider this.)
As someone said [1] on the internet:
Say ".yaml" not ".yml".
This is not MS-DOS, and YML is a Yahoo XML dialect.
Similarly, we use '.json', not '.jsn'.
[1]: https://github.com/ceph/s3-tests/commit/e17c56a
