Include of package.json should be also possible for non google provider

[SaschaKuhnigk]

Hello,

the possiblity to include the package.json might be helpful for at least two use cases:

• communicate the module system to the lambda environment
• some libs read information from this file (e.g. @probot/adapter-aws-lambda-serverless)

I am wondering why the file package.json and some more are explicitly excluded...

Does someone have any idea for the reason behind this decision?