Add copyright notice to module where unsplit is used.

src/syn_netsplits.erl

@@ -2,6 +2,9 @@
 %% Syn - A global process registry.
 %%
 %% Copyright (C) 2015, Roberto Ostinelli <roberto@ostinelli.net>.
+%% Portions of code from Ulf Wiger's unsplit server module:
+%% <https://github.com/uwiger/unsplit/blob/master/src/unsplit_server.erl>
+%%
 %% All rights reserved.
 %%
 %% The MIT License (MIT)