rig_in_namespace() to be able to reset, add, remove

[moodymudskipper]

from #16 :

Right now we need to restart the session (or devtools::load_all() if only rigging in developped package).

Still not sure what would be the best way, maybe we'd need unrig_in_namespace(), that unrigs eveything if no arg is given (we'd need to keep an index of rigged functions), and have rig_in_namespace() add as it does now, but make sure we cannot rig a function 2 times.

Or we might have rig_in_namespace() work a bit like dplyr::select()

[krlmlr]

Often, the workflow is to rig, change the code, rerun. When we change the code, we need load_all() anyway. I'd say the current solution works fine as is?

[moodymudskipper]

It works fine for package development with devtools, but if one wants to rig a function from another package one needs to restart R and that's less comfortable. Moreover not being able to rig a function two times would have helped me already.

You're right though and it's not high priority but I don't think it's too hard to implement.