Implements: #80 #81

Closes #80 (closed) #81 (closed)

lib/bma/blockchain/with/leavers.ex

 defmodule BMA.Blockchain.With.Leavers do
     def get do
-        Poison.encode!("#TODO")
+        {:ok, blocks} = :dets.open_file(:block , [{:file, 'data/block'} , {:type, :set}])
+        result = []
+        result = result ++ :dets.traverse(
+            :block,
+            fn {_, value} ->
+              if(value["leavers"]) != []) do
+                  {:continue, value["number"]}
+              else
+                  :continue
+              end
+            end
+                 )
+        JSON.encode!([result: [blocks: result]])
     end
-end
\ No newline at end of file
+
+end