Tidy up ConfigurationSource a bit

Believe it or not, this (where mainly I move some code from arti to arti-config) is part of dismantling arti-config (part of #456 (closed))

assigned to @Diziet

PS: I have just realised that this is missing the semver note update. I will add a commit for that.

requested review from @nickm

LGTM; just needs semver note and merge conflict fixes.

approved this merge request

added 1 commit

• 2b10f56d - Document semver changes to ConfigurationSources etc.

Compare with previous version

added 47 commits

• 2b10f56d...0597c31a - 40 commits from branch tpo/core:main
• 618d04d5 - ConfigurationSource: Rename new to new_empty
• 46f8b240 - tor-config: Export CfgPathError
• 43068257 - default_config_file(): Have it return Result, not Option
• 6337ad2f - ConfigurationSource: Move "usual" logic for construction
• c01d28b2 - ConfigurationSources: Have the generics take Into<owned>
• 4d805928 - Move default_config_file() into arti-client
• cb8f6e20 - Document semver changes to ConfigurationSources etc.

Compare with previous version

Well, my main was rather out of date when I started this, apparently. The changes weren't entirely trivial. The main one was that ConfigurationSource::from_cmdline now takes a Mistrust.

I will "request re-review" but feel free to just merge it if you don't feel the need to recheck it.

added 9 commits

• cb8f6e20...cc3ec808 - 2 commits from branch tpo/core:main
• e363b79a - ConfigurationSource: Rename new to new_empty
• 26b31155 - tor-config: Export CfgPathError
• 93da6129 - default_config_file(): Have it return Result, not Option
• c9fee15c - ConfigurationSource: Move "usual" logic for construction
• c76c79d0 - ConfigurationSources: Have the generics take Into<owned>
• 8fe62da8 - Move default_config_file() into arti-client
• 775432be - Document semver changes to ConfigurationSources etc.

Compare with previous version

enabled an automatic merge when the pipeline for 775432be succeeds

still lgtm; marking to merge.

mentioned in issue #472 (closed)

merged

mentioned in commit b137be22