[Agda] Redundant imports

[Martín Hötzel Escardó]

I have reorganized a large code base by splitting and merging modules, 
and moving things from one module to another, and I fear I am left with 
very many redundant imports. Is there any way to detect them 
automatically? This is important to try speed up "reloading" in 
interactive mode. (Although already this refactoring has improved this bit.)

Thanks,
Martin