Add main.workflow

Author: pmarsceill

.github/main.workflow

@@ -0,0 +1,16 @@
+workflow "Publish to RubyGems" {
+  on = "release"
+  resolves = ["scarhand/actions-ruby@master"]
+}
+
+action "Build from Gemspec" {
+  uses = "scarhand/actions-ruby@master"
+  runs = "build just-the-docs.gemspec"
+}
+
+action "scarhand/actions-ruby@master" {
+  uses = "scarhand/actions-ruby@master"
+  needs = ["Build from Gemspec"]
+  runs = "push *.gem"
+  secrets = ["RUBYGEMS_AUTH_TOKEN"]
+}