Merge pull request #362 from ricemery/grade-school

Add file with expected interface. Refs #137

Author: ErikSchierboom

exercises/grade-school/src/main/scala/School.scala

@@ -0,0 +1,11 @@
+class School {
+  type DB = Map[Int, Seq[String]]
+
+  def add(name: String, g: Int) = ???
+
+  def db: DB = ???
+
+  def grade(g: Int): Seq[String] = ???
+
+  def sorted: DB = ???
+}