allow Erlang 19

Author: danikp

rebar.config

@@ -8,7 +8,7 @@
         {ibrowse, "", {git, "git://github.com/cmullaparthi/ibrowse.git", {tag, "v4.1.2"}}}
        ]}.
 
-{require_otp_vsn, "R16|17|18"}.
+{require_otp_vsn, "R16|17|18|19"}.
 
 {erl_opts, [
             fail_on_warning,