[CDN] Set override url for CDN hosted files

[tonhuisman]

Feature:

Set a user-specific url for the .js and .css files, normally hosted at a CDN (Content Delivery Network, jsdelivr.net) or included in the build (MAX).

• Add configuration setting on the Config page (settings file customcdnurl.dat will be removed if setting is empty) (NB: Changed filename from initial commit)
• Update documentation

TODO:

• Support in Provisioning feature
• Update documentation
• Add support for system variables in Custom CDN url
• Improve command handling for Provisioning commands
  • Add temporary fall-back to old commands for MAX builds

[chromoxdor]

Add configuration setting on the Config page (settings file customcdnurl.dat will be removed if setting is empty) (NB: Changed filename from initial commit)

@tonhuisman, I wanted to test this feature but could not find it. Or did i got it all wrong. From my understanding there should now an extra field in /config for this? 🤷‍♂️

[tonhuisman]

Yes, but only for builds that don't have the .js/.css embedded in the .bin file like the MAX builds and Custom builds that have their own CDN url defined (not in the standard build sets, AFAIK)

[TD-er]

At the bottom of src/src/CustomBuild/define_plugin_sets.h I have this in comments, which I used for testing myself:

// TODO TD-er: Test feature, must remove
/*
#ifdef FEATURE_ALTERNATIVE_CDN_URL
#undef FEATURE_ALTERNATIVE_CDN_URL
#endif
#define FEATURE_ALTERNATIVE_CDN_URL 1
*/