Use released version of gen_smtp, with iconv fixes

See gen-smtp/gen_smtp#177

Author: MonsieurV

rebar.config

@@ -12,7 +12,7 @@
 
 {deps, [
     {eiconv, "1.0.0-alpha1"},
-    {gen_smtp, "0.14.0", {git, "git://github.com/gen-smtp/gen_smtp.git", {branch, "master"}}},
+    {gen_smtp, "0.15.0"},
     {jsone, "1.4.7"},
     {nested, "0.1.2"},
     {hackney, "1.13.0"},

rebar.lock

@@ -2,10 +2,7 @@
 [{<<"backoff">>,{pkg,<<"backoff">>,<<"1.1.6">>},0},
  {<<"certifi">>,{pkg,<<"certifi">>,<<"2.3.1">>},1},
  {<<"eiconv">>,{pkg,<<"eiconv">>,<<"1.0.0-alpha1">>},0},
- {<<"gen_smtp">>,
-  {git,"git://github.com/gen-smtp/gen_smtp.git",
-       {ref,"894cf847abece28b3bda90632ed9ed04fe8ea8a1"}},
-  0},
+ {<<"gen_smtp">>,{pkg,<<"gen_smtp">>,<<"0.15.0">>},0},
  {<<"goldrush">>,{pkg,<<"goldrush">>,<<"0.1.9">>},1},
  {<<"hackney">>,{pkg,<<"hackney">>,<<"1.13.0">>},0},
  {<<"idna">>,{pkg,<<"idna">>,<<"5.1.2">>},1},
@@ -23,6 +20,7 @@
  {<<"backoff">>, <<"83B72ED2108BA1EE8F7D1C22E0B4A00CFE3593A67DBC792799E8CCE9F42F796B">>},
  {<<"certifi">>, <<"D0F424232390BF47D82DA8478022301C561CF6445B5B5FB6A84D49A9E76D2639">>},
  {<<"eiconv">>, <<"547DA4B8ABB5C85EE8E47D7B9EBFCA77016B03F2869DEDC91A0F0177AB67EBC4">>},
+ {<<"gen_smtp">>, <<"9F51960C17769B26833B50DF0B96123605A8024738B62DB747FECE14EB2FBFCC">>},
  {<<"goldrush">>, <<"F06E5D5F1277DA5C413E84D5A2924174182FB108DABB39D5EC548B27424CD106">>},
  {<<"hackney">>, <<"24EDC8CD2B28E1C652593833862435C80661834F6C9344E84B6A2255E7AEEF03">>},
  {<<"idna">>, <<"E21CB58A09F0228A9E0B95EAA1217F1BCFC31A1AAA6E1FDF2F53A33F7DBD9494">>},