Support config file location param

[milindgoel15]

As per docs, the package_rename_config should be kept inside pubspec or at the project's root. Can the command accept a path for the config file? I like keeping all config files in one folder, not the root folder.

Like dart run package_rename --config config/package_rename_config.yaml

[OutdatedGuy]

I will provide a feature for that as I get time

[milindgoel15]

I will also try it out and create a PR for it.

[OutdatedGuy]

@milindgoel15, published in version 1.5.0