Avoid InitError on Julia 1.3 with system MPI libraries (#456)

* Avoid InitError on Julia 1.3 + Unix + system MPI
* Add version check

Author: jipolanco

src/implementations.jl

@@ -10,7 +10,8 @@ macro mpicall(expr)
 
     # On unix systems we call the global symbols to allow for LD_PRELOAD interception
     # It can be emulated in Windows (via Libdl.dllist), but this is not fast.
-    if Sys.isunix() && expr.args[2].head == :tuple
+    if Sys.isunix() && expr.args[2].head == :tuple &&
+            (VERSION ≥ v"1.5-" || expr.args[2].args[1] ≠ :(:MPI_Get_library_version))
         expr.args[2] = expr.args[2].args[1]
     end