progress reporting when loading a large number of modules

[Wizek]

Similar to what ghc(i) does [ 1 of 39] Compiling .... Could be as simple as an IORef that gets updated with a tuple (1, 39), or a nicer API if someone has a better idea. At the moment loading about 39 modules can take somewhere between 10-30 seconds, being able to show progress to end users would be quite nice.

[mvdan]

If ghci can do it, it's very likely that it could be exposed in this API somehow. I don't have much time for this project these days, though.

[gelisam]

(I didn't remove the "help wanted" tag because help is no longer wanted, but because that tag is redundant; I welcome help on all the issues, not just those which have the "help wanted" tag!)