Allow seoGoogleTagManager property to be overridden from settings in data/local.js

[shaunhurley]

Sample solution to close #50

Allow seoGoogleTagManager property to be overridden from settings in data/local.js such that specific Google Tag Managers can be enforced in specific environments i.e. dev/test

I've set this up to use a generic 'settings' module as discussed at here but it could presumably just as easily be included in an apostrophe-global section (in line with the existing directives) or an apostrophe-seo section to keep the functionality together?

[abea]

Thanks for this @shaunhurley. Apologies for my taking so long to review it.

Besides the implementation note, this would need documentation in the README. We'd also need the same for the other Google properties, but you probably planned that. This looks like a draft implementation.

I think this would be useful not only for your case but to allow the Google properties to be hard coded in the environment if desired, keeping it out of the UI altogether. It's not the best for everyone, but could be useful for some organizations.

@boutell Do you have thoughts on the general idea?

[abea]

This would need to be on a module we know will be there and that has an alias to reference this way. With that in mind I'd use the SEO module and assign it an alias such as aposSeo.

I'm not sure it needs the seoOverRides layer. You could simply add the option directly on the module. That also saves you having to write an additional conditional below to see if seoOverRides exists.