Add support to delete a team

Add a method to delete a team.

src/main/java/org/kohsuke/github/GHTeam.java

@@ -126,6 +126,13 @@ public void add(GHRepository r) throws IOException {
     public void remove(GHRepository r) throws IOException {
         org.root.retrieve().method("DELETE").to(api("/repos/" + r.getOwnerName() + '/' + r.getName()), null);
     }
+
+    /**
+     * Deletes this team.
+     */
+    public void delete() throws IOException {
+        org.root.retrieve().method("DELETE").to(api(""));
+    }
 
     private String api(String tail) {
         return "/teams/"+id+tail;