Resolve env loading and multi channel publishing

[darrenbelding]

What? Why?

Multi-channel widget publishing wasn't working. There were two separate problems here:

• Environment variables are loaded using dotenv but only inside authConfig. Due to the way ES6 module resolution and eval works, any env vars referenced outside this file would return undefined. Therefore, only default values were ever loaded. Channels other than 1 did not work!
• Widget templates required matching to channel ids so that they update the correct template when using different templates/widget instances on different channels