Feature/refactor env file writer local

Merge branch 'feature/refactor-env-file-writer-local' of https://bitbucket.org/johnsvenn/platform into feature/refactor-env-file-writer-local

* 'feature/refactor-env-file-writer-local' of https://bitbucket.org/johnsvenn/platform:
  Refactor EnvFileWriter and associated files

Update EnvFileWriter so that it can be used to write any of the variables to the .env file not just the database connection variables. This means that it will be possible to easily and consistently add prompts for additional variables going forwards (e.g. APP_URL). Additionally, update ConfigureDatabase and SetInstalled flag so that they both use the updated CreateEnvFile. The .env file is now created by CreateEnvFile.

Edit grid error solution

Solution for this.spawn_widget is not a function

Update EnvFileWriter so that it can be used to write any of the variables to the .env file not just the database connection variables. This means that it will be possible to easily and consistently add prompts for additional variables going forwards (e.g. APP_URL). Additionally, update ConfigureDatabase and SetInstalled flag so that they both use the updated CreateEnvFile. The .env file is now created by CreateEnvFile.