third_party/go: add gostatic

To test:

    bazel run '@com_github_piranha_gostatic//:gostatic'

Change-Id: Ie846429df0d1f1914f2734735591edebd5d29094

third_party/go/repositories.bzl

@@ -1717,3 +1717,27 @@ def go_repositories():
         commit = "a606d617e1d1546a2342de6fc4ed95c78e171d68",
         importpath = "github.com/kevinburke/go-bindata",
     )
+
+    go_repository(
+        name = "com_github_yuin_goldmark",
+        importpath = "github.com/yuin/goldmark",
+        sum = "h1:ruQGxdhGHe7FWOJPT0mKs5+pD2Xs1Bm/kdGlHO04FmM=",
+        version = "v1.2.1",
+    )
+
+    go_repository(
+        name = "com_github_jessevdk_go_flags",
+        importpath = "github.com/jessevdk/go-flags",
+        sum = "h1:4IU2WS7AumrZ/40jfhf4QVDMsQwqA7VEHozFRrGARJA=",
+        version = "v1.4.0",
+    )
+
+    # gostatic at 2.24. Unfortunately upstream doesn't follow semver tagging in `vx.y.z` form,
+    # thereby prohibiting usage of a gomod version directly in the version attribute of this
+    # rule.
+    go_repository(
+        name = "com_github_piranha_gostatic",
+        importpath = "github.com/piranha/gostatic",
+        sum = "h1:GfShSQ+2DojR7GRI5wPByszs93zHXW2zOT0SuHadaaa=",
+        version = "v0.0.0-20200923134324-2.24",
+    )