copy preserves type (#273)

fixes #214

Author: andyferris

src/abstractarray.jl

@@ -121,7 +121,7 @@ reshape(a::Array, s::Size{S}) where {S} = s(a)
 
 @inline vec(a::StaticArray) = reshape(a, Size(prod(Size(typeof(a)))))
 
-@inline copy(a::StaticArray) = similar_type(a)(Tuple(a))
+@inline copy(a::StaticArray) = typeof(a)(Tuple(a))
 
 # TODO permutedims?