Adds logging to cask loader

[apainintheneck]

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The idea here is to make it easier to debug any cask loading problems in the future. We already have similar logging in place in Formulary.

Changes

• extend Context to get debug? method
• create FromDefaultTapPathLoader to handle expected loading option
  • Note: This is a common case and it allows it to be logged as well.
• log cask loader used when --debug

Examples

Without --debug:

$ brew install -n --cask 1password
==> Would install 1 cask:
1password

With --debug:

$ brew install -n --cask "$(brew --repo)/Library/Taps/homebrew/homebrew-cask/casks/1password.rb" --debug
/usr/local/Homebrew/Library/Homebrew/brew.rb (Cask::CaskLoader::FromTapPathLoader): loading /usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask/casks/1password.rb
==> Would install 1 cask:
1password

/u/l/Homebrew (add-logging-to-cask-loader|✔) $ brew install -n --cask homebrew/cask/1password --debug
/usr/local/Homebrew/Library/Homebrew/brew.rb (Cask::CaskLoader::FromTapLoader): loading homebrew/cask/1password
==> Would install 1 cask:
1password

/u/l/Homebrew (add-logging-to-cask-loader|✔) $ brew install -n --cask 1password --debug
/usr/local/Homebrew/Library/Homebrew/brew.rb (Cask::CaskLoader::FromDefaultTapPathLoader): loading 1password
==> Would install 1 cask:
1password

[BrewTestBot]

Review period will end on 2023-02-07 at 00:00:00 UTC.

[Rylan12]

Thanks, looks good! This will be helpful

[MikeMcQuaid]

Love this, thanks @apainintheneck!

[BrewTestBot]

Review period skipped due to critical label.