adding centrality example

examples/greatest.rb

@@ -0,0 +1,43 @@
+require 'rubygems'
+require 'neography'
+
+def create_great(name)
+  Neography::Node.create("name" => name)
+end
+
+game      = create_great('The 1958 NFL Championship Game')
+brando    = create_great('Marlon Brando')
+alex      = create_great('Alexander the Great')
+circus    = create_great('The Ringling Bros. and Barnum and Bailey')
+beatles   = create_great('The Beatles')
+ali       = create_great('Muhammad Ali')
+bread     = create_great('Sliced Bread')
+gatsby    = create_great('The Great Gatsby')
+
+greats = [game,brando,alex,circus,beatles,ali,bread,gatsby]
+
+def as_great(great, other_greats)
+  other_greats.each do |og|
+    great.outgoing(:as_great) << og
+  end
+end
+
+greats.each do |g|
+  ogs = greats.select{|v| v != g }.sample(1 + rand(5))
+  as_great(g, ogs)
+end
+
+def the_greatest
+  neo = Neography::Rest.new
+  neo.execute_script("m = [:];
+                      c = 0;
+                      g.
+                        V.
+                        out.
+                        groupCount(m).
+                        loop(2){c++ < 1000}.iterate();
+                        
+                        m.sort{a,b -> b.value <=> a.value}.keySet().name[0];")
+end
+
+puts "The greatest is #{the_greatest}"