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The --open flag is now more of a 'force' open. When mix docs.dash is called, the docset is opened automatically, unless a docset with the exact name already exists (in that case, the docs update under the hood, but do not need to be re-opened in Dash for the updates to be realized).

The --name NAME param now defaults to setting umbrella project names to the result of File.cwd!() |> Path.basename(), as this is likely the desired project name anyway.

An --abbr ABBR option can be passed to set a custom abbreviation. This can also be edited in Dash's preferences pane by hand. This only works when the docset is first added to Dash - after that, it must be updated via Dash or fully removed and readded.

Margin tweaks

Alignment in Dash browser matches docs from hex.

Don't overwrite app name

Fixes logic that was overwriting app names unless --name was set.