Create file with snippets for all API read methods

This file contains snippets generated using default parameter values in the API code snippet tool at https://devsite.googleplex.com/youtube/v3/code_samples/code_snippets. The file contains the boilerplate code for Apps Script, which is a basic function that prints some output from each API response to the logging console as well as all of the snippets for the API methods. Currently, the functions cover all of the API's read-only methods.