prelude: Remove redundant reexports (and their imports) already provided by other preludes
For cleanliness the prelude module only needs to reexport preludes from direct, "top-most" crates, which themselves take care of reexporting preludes from its dependencies again. This shaves off some code while maintaining the same set of exports.
When importing the prelude of a crate like gst
the glib
prelude is
provided too. Shedding these imports saves quite a few lines and
adheres to keeping it simple; we're not reexporting base/parent preludes
for no reason :)
Had this sitting in my stash since monday, I hope you appreciate cleanup noise like this @slomo :)