Add bin and edit workflow

bin/gems/facets-3.1.0/lib/standard/facets/math/delta.rb

@@ -0,0 +1,9 @@
+module Math
+
+  # Kronecker symbol of +i+ and +j+.
+  # Returns 1 if +i+ and +j+ are equal, 0 otherwise.
+  def self.delta(i, j)
+    return Integer(i) == Integer(j) ? 1 : 0
+  end
+
+end