fix atoms in branch names

rebar.config

@@ -1,3 +1,4 @@
 {deps, [
-        {getopt, ".*", {git, "git://github.com/jcomellas/getopt.git", {tag, "v0.8.2"}}}
+        {getopt, ".*",   {git, "git://github.com/jcomellas/getopt.git", {tag, "v0.8.2"}}},
+        {goldrush, ".*", {git, "https://github.com/metachord/goldrush.git", master}}
        ]}.

src/mad_deps.erl

@@ -73,7 +73,7 @@ build_dep(Cwd, Conf, _ConfFile, Publisher, Name, Cmd, Co) ->
     mad_utils:exec("cp", ["-r", TrunkPath, DepsDir]),
     %% change cwd to the copy of trunk and checkout to Co
     ok = file:set_cwd(DepsDir),
-    mad_utils:exec(Cmd, ["checkout", Co]),
+    mad_utils:exec(Cmd, ["checkout", lists:concat([Co])]),
     ok = file:set_cwd(Cwd).
 
 %% internal