Reset entire module cache on change to any file that is part of the project

[jkelvie]

Per these changes on the serverless-plugin:
https://github.com/breathe/serverless-plugin-bespoken/blob/ea4ed854f91cb569862c4cf9f1016ba349a3083c/src/ServerlessPluginBespoken.ts#L20

And per this discussion:

I believe the best course is to fully reset the cache, regardless of what directory it is in (though we still want to exclude node_modules), when any file that is part of the project has changed.

This means, when we detect a change in ModuleManager:

• resetCache on NodeUtil can be called right away
• There is no need for a dirty flag
• We should not need the modules variable either - instead calling module should just immediately call require(filePath)

In this way, we can significantly simplify the logic while improving the functionality.

[dmarvp]

@jkelvie @jperata is this still valid as of today?

[jkelvie]

It is still valid. The behavior we would like is that any time a file changes in the project, the modules cache is completely replaced.

Currently, when someone changes a file OTHER than the main lambda, the change is only "hot-loaded" when the user happens to also change the main lambda (i.e., index.js).