Merge source app.js methods into target app.js

[KenEucker]

Now that we are forming a structure for the app.js model, including lifecycle methods, we can implement polymorphism to load the downloaded sourcefiles app.js methods in a chain operation.

IE:
The BikeTag Website project has source files from the BikeTag App project. The final deployed solution, biketag-infra, which uses the BikeTag Website as it's source, would end up with the files:

app.js
biketag-website.app.js
biketag-app.app.js

app.js pseudocode:

import sexpress
import biketag-website as biketagWebsite
import biketag-app as biketagApp

class sexpressApplication {

  onConfigurationLoad: (siteConfig) => {

     let finalSiteConfiguration = siteConfig
     finalSiteConfiguration = { ...finalSiteConfiguration, ...biketagWebsite.onConfigurationLoad(finalSiteConfiguration) }
     finalSiteConfiguration = { ...finalSiteConfiguration, ...biketagApp.onConfigurationLoad(finalSiteConfiguration) }

     return finalSiteConfiguration
  }

  onPageDataRequest: (siteConfig) => {

     let finalPageData = siteConfig
     finalPageData = { ...finalPageData, ...biketagWebsite.onPageDataRequest(finalPageData) }
     finalPageData = { ...finalPageData, ...biketagApp.onPageDataRequest(finalPageData) }

     return finalPageData

  }

  onAppStart: () => {
    biketagWebsite.onAppStart()
    biketagApp.onAppStart()
  }

  run: () => {
    const app = sexpress(this)
    app.run(this.onAppStart)

    return this
  }

}

const applicationInstance = new sexpressApplication().run()

This feature should change the existing "generate" config from the following fields:

...
  "source": "https://github.com/biketagorg/biketag-app/archive/production.zip",
  "templatesSource": "https://github.com/biketagorg/biketag-website/archive/production.zip"
...

to:

  "applicationChain": [
    "https://github.com/biketagorg/biketag-website",
    "https://github.com/biketagorg/biketag-app"
  ]

The feature outlined above will aid the deployment of mode-based seXpress application subsets and combinations.

[KenEucker]

In fact, all of these options should change to suit the new application chaining feature:

		"enabled": true,
		"copyServerFile": true,
		"copyControllers": true,
		"copyLib": true,
		"copySrc": true,
		"copyConfigJs": true,
		"copySourceConfig": false,
		"copyTemplateConfig": true,
		"importDependencies": true,
		"keepExistingDepdencyVersions": true,
		"copyPrivateConfig": true,

And instead should become single application environment variables, configured like so:

  "applicationChain": {
    "https://github.com/biketagorg/biketag-website": {
      "copyConfigJs": true,
      "copyLib": false,
      "copySrc": false,
      "keepExistingDepdencyVersions": true,
    },
    "https://github.com/biketagorg/biketag-app": {
      "copyConfigJs": false,
      "copyLib": true,
      "copySrc": true,
      "keepExistingDepdencyVersions": false
    }
  }