Check for configuration updates
Description
This change will prompt GDK users when the underlying GDK config template changes.
This approach is already used for unicorn.rb and puma.rb files, and this change extends the concept to all configuration files in GDK.
This means that we a change is made to a configuration file in GDK, the local file will be overwritten with the change, except if the user has made changes locally, in which case the user will receive a notification stating that their local configuration is out of date.
Why do we want this?
Currently, when a change is made to GDK, auxiliary configuration files do not automatically get updated without a gdk reconfigure.
This means that there can be inconsistencies in the config.
For example, for the upcoming introduction of Jaeger. GDK makes changes to the Procfile, and these changes are reflected in the UI of the application (which contains links to the Jaeger UI). Unfortunately the GDK user needs to make the manual step of running gdk reconfigure otherwise the application will not work as expected.
But what if I make local changes?
- Local changes are fine and will not be overwritten
- When the local change is newer than the template, no warnings will be generated
- When the local change is older than the template, a warning will be issued and a diff comparing old and new will be shown