Tracks Angular environment specific files as entry points.

Takes into account:

• If file replacements are part of a production configuration or not to add them as production entries or not.
• Previous syntax for Webpack-based browser application builder (src/replaceWith instead of replace/with).
• File replacements out of configurations. As they're technically correct and work. However, it's not a common use case. The purpose of environment files is to apply different ones depending on the configuration, not apply them for all cases (hence part of the builder options). Also those aren't used if a configuration specifies some fileReplacements.