[FR]: provide default exclude_package_contents similar to yarn autoclean

[jbedard]

The exclude_package_contents feature should have reasonable defaults similar to yarn autoclean, see https://github.com/yarnpkg/yarn/blob/7cafa512a777048ce0b666080a24e80aae3d66a9/src/cli/commands/autoclean.js#L16

exclude_package_contents could have a default ["*"] entry similar to the yarn defaults that users can then override with another "*" entry or with package specific excludes.