Added forward compatibility aliases for JuliaLang#8175

After renaming some constants in JuliaLang#8175, it became harder to write the
same code to target 0.3.x and 0.4-dev. This PR potentially adds aliases,
so that when 0.3.1 gets released, less mainanance intrested package
authors can drop support for 0.3.0, and be compatible with both 0.3.1
and 0.4-dev with the same code base, without version conditionals.

Author: ivarne

Diff for: base/deprecated.jl

@@ -159,3 +159,11 @@ scale!{T<:Base.LinAlg.BlasReal}(X::Array{T}, s::Complex) = error("scale!: Cannot
 
 @deprecate which(f::Callable, args...) @which f(args...)
 @deprecate rmdir rm
+
+
+# 0.4 compatibility utilities (to simplify 0.4/0.3.1 compatibility)
+
+export TCPSocket, UDPSocket, IPAddr
+const TCPSocket = TcpSocket
+const UCPSocket = UdpSocket
+const IPAddr = IpAddr