Simple configuration for Keep a Changelog style changelogs

[matteosantama]

Description

Fixes #691

This PR simplifies the configuration for Markdown changelog files. The directory key is inferred from the name key, and showcontent defaults to true.

Checklist

• Make sure changes are covered by existing or new tests.
• For at least one Python version, make sure test pass on your local environment.
• Create a file in src/towncrier/newsfragments/. Briefly describe your
  changes, with information useful to end users. Your change will be included in the public release notes.
• Make sure all GitHub Actions checks are green (they are automatically checking all of the above).
• Ensure docs/tutorial.rst is still up-to-date.
• If you add new CLI arguments (or change the meaning of existing ones), make sure docs/cli.rst reflects those changes.
• If you add new configuration options (or change the meaning of existing ones), make sure docs/configuration.rst reflects those changes.

[adiroiban]

Thanks Matteo for the PR.
It looks good.

Let me know when the PR is ready for review and I will do a full review.

[matteosantama]

As it stands this PR closes #691. Would you like to see it include #692 as well, or should that follow in a separate PR?

[adiroiban]

Many thanks for the fix.

The change looks good.

A few minor comments.

The major comment is on what is checked/asserted by the tests.

I think that we should check more than just the exit code for build --draft.

Thanks again!

[adiroiban]

Would you like to see it include #692 as well, or should that follow in a separate PR?

Definetely a separate PR.

We should keep tihs PR as small as possible so that we can merge it as fast as possible.

#692 might need some discussions and considerations before a merge

Thanks

[adiroiban]

We can leave it as it is. Just a sidenote

I am not sure that it helps to repeate the actual value here.

Of we want to show full diff, we can set unittest.TestCase.maxDiff

Suggested change

	self.assertEqual(expected, news, news)
	self.assertEqual(expected, news, news)

[adiroiban]

Stellar work! I will merge.

Thanks again