Make possible to explicitly request "parameters"

[sebhoerl]

Currently, a stage like this will obtain either a value that has directly been passed by a child stage or a value that comes from the global pipeline configuration:

def configure(context):
   value = context.config("abc")

In some cases, we don't want to rely on the global pipeline configuration (because we want to explicitly make sure that this stage is called with a well-chosen argument). Currently, there is no way to enforce a parameter to by passed from another stage rather from global configuration. Therefore, I'd propose to have:

def configure(context):
   value = context.config("abc", parameter = True)

In this case the option becomes a "parameter" to the stage. This requires some moving around of code internally in the pipeline, but should not be awfully complicated.

[davibicudo]

I faced an issue where synpp crashes in cases where both parent and child have different setting for a parameter with the same name, e.g. "write_output" is False for child but for parent it is True. This enhancement could also fix it.

[sebhoerl]

Yeah, I guess that it crashes currently is good, as the values should be passed down, and otherwise we get a mix-up. So yes, this could be a solution, because it makes it explicit. And when some config value is a "parameter" we should require that it is passed explicitly. I can have a look at it at some point. Or do you want to give it a try? :)

[davibicudo]

Currently I'm tight on time for anything non mission-critical, but I'd surely be glad to contribute here eventually. I'll let you know beforehand :)