update relx version. fixes #434

rebar.config

@@ -10,7 +10,7 @@
          {tag, "v1.3.1"}}},
        {relx, "",
         {git, "https://github.com/erlware/relx.git",
-         {tag, "v2.0.0"}}},
+         {branch, "master"}}},
        {mustache, ".*",
          {git, "https://github.com/soranoba/mustache.git",
           {tag, "v0.3.0"}}},

rebar.lock

@@ -1,6 +1,6 @@
 [{<<"relx">>,
   {git,"https://github.com/erlware/relx.git",
-       {ref,"2e59b1c95575b3c104cc191e954c82baadc43c6c"}},
+       {ref,"74fec3455ba6dbb7d9e369137c1b15ab10804993"}},
   0},
  {<<"providers">>,
   {git,"https://github.com/tsloughter/providers.git",