buildGoPackage: remove Go deps file libs.json

After #16017 there were a lot
of comments saying that `nix` would be better than `JSON`
for Go packages dependency sets.
As said in https://github.com/NixOS/nixpkgs/pull/16017#issuecomment-229624046

    > Because of the content-addressable store, if two programs have the
    > same dependency it will already result in the same derivation in
    > the
    > store. Git also has compression in the pack files so it won't make
    > much difference to duplicate the dependencies on disk. And finally
    > most users will just use the binary builds so it won't make any
    > differences to them.

This PR removes `libs.json` file and puts all package dependencies in
theirs `deps.json`.

pkgs/servers/interlock/deps.json

@@ -1,14 +1,65 @@
 [
-  {
-    "include": "../../../go-modules/libs.json",
-    "packages": [
-      "github.com/Sirupsen/logrus",
-      "github.com/agl/ed25519",
-      "github.com/golang/protobuf",
-      "github.com/janimo/textsecure",
-      "golang.org/x/crypto",
-      "golang.org/x/net",
-      "gopkg.in/yaml.v2"
-    ]
-  }
+    {
+        "goPackagePath": "gopkg.in/yaml.v2",
+        "fetch": {
+            "type": "git",
+            "url": "https://gopkg.in/yaml.v2",
+            "rev": "a83829b6f1293c91addabc89d0571c246397bbf4",
+            "sha256": "1m4dsmk90sbi17571h6pld44zxz7jc4lrnl4f27dpd1l8g5xvjhh"
+        }
+    },
+    {
+        "goPackagePath": "golang.org/x/crypto",
+        "fetch": {
+            "type": "git",
+            "url": "https://go.googlesource.com/crypto",
+            "rev": "575fdbe86e5dd89229707ebec0575ce7d088a4a6",
+            "sha256": "1kgv1mkw9y404pk3lcwbs0vgl133mwyp294i18jg9hp10s5d56xa"
+        }
+    },
+    {
+        "goPackagePath": "github.com/Sirupsen/logrus",
+        "fetch": {
+            "type": "git",
+            "url": "https://github.com/Sirupsen/logrus",
+            "rev": "be52937128b38f1d99787bb476c789e2af1147f1",
+            "sha256": "1m6vvd4pg4lwglhk54lv5mf6cc8h7bi0d9zb3gar4crz531r66y4"
+        }
+    },
+    {
+        "goPackagePath": "github.com/agl/ed25519",
+        "fetch": {
+            "type": "git",
+            "url": "https://github.com/agl/ed25519",
+            "rev": "278e1ec8e8a6e017cd07577924d6766039146ced",
+            "sha256": "165d89cc6dl28j4hkn86pny0jz3sa6hamzdvpvwdj4iha3x6lzc9"
+        }
+    },
+    {
+        "goPackagePath": "github.com/golang/protobuf",
+        "fetch": {
+            "type": "git",
+            "url": "https://github.com/golang/protobuf",
+            "rev": "59b73b37c1e45995477aae817e4a653c89a858db",
+            "sha256": "1dx22jvhvj34ivpr7gw01fncg9yyx35mbpal4mpgnqka7ajmgjsa"
+        }
+    },
+    {
+        "goPackagePath": "github.com/janimo/textsecure",
+        "fetch": {
+            "type": "git",
+            "url": "https://github.com/janimo/textsecure",
+            "rev": "c38f429e48d6b2776d17b4171f216f132185b0f6",
+            "sha256": "191pwgfgphr0x04dwpvniax4wilpv52l25bw7d3igvnw302y7i94"
+        }
+    },
+    {
+        "goPackagePath": "golang.org/x/net",
+        "fetch": {
+            "type": "git",
+            "url": "https://go.googlesource.com/net",
+            "rev": "62ac18b461605b4be188bbc7300e9aa2bc836cd4",
+            "sha256": "0lwwvbbwbf3yshxkfhn6z20gd45dkvnmw2ms36diiy34krgy402p"
+        }
+    }
 ]