String: alias for new String or old UTF8String

Author: StefanKarpinski

src/Compat.jl

@@ -1077,4 +1077,12 @@ if !isdefined(Base, :Threads)
     export Threads
 end
 
+if isdefined(Core, :String)
+    typealias String Core.String
+    export String
+else
+    typealias String Base.UTF8String
+    export String
+end
+
 end # module