Define copy for Char

[bkamins]

I suggest to define copy for Char. Otherwise operations like 'a'^1 throw an error.

[ararslan]

Kind of a weird definition to have, but we have it for numbers, so ¯\_(ツ)_/¯

[bkamins]

exactly, but some code assumes it.

[StefanKarpinski]

Repeating characters works just fine:

julia> 'a'^1
"a"

I'm not against this but @JeffBezanson had some rather strong objections the last time copy methods for immutable types came up.

[bkamins]

Sorry - I had Julia 0.7 before e596847 installed. Yes - now it works correctly 👍. So I am indifferent to this PR. On the other hand deepcopy works on Char now.

[ararslan]

If 'a'^1 works now, I think I'd prefer we not do this. The fewer sketchy copy definitions the better, IMO.

[TotalVerb]

Since strings are immutable too, and need not be copyed, I don't understand why this is needed. With numbers the argument can be made for compatibility with arrays.

[JeffBezanson]

Adding this wouldn't be the end of the world, but since the original motivation no longer applies I'll close this for now.