Remove readme files?

[izahn]

I notice that as we use this template we usually don't bother to update all the readme files. This creates two problems: it misleads people into thinking we have something to tell them (else why would we have a readme? and it clutters up commit histories. We could eliminate the second problem by keeping files but removing all content from them, but we would still have the first problem (readme's that don't actually need to be read because they just contain uninformative boilerplate).

Proposal: remove all readme files except for the one in the top level. Thoughts @mbsabath ?

[mbsabath]

I think that makes sense. Maybe we can take the language from the internal readmes in to the top level one.