Add FinancialLinks

For now this is only usefull for plugins, since there is no UI.

app/models/financial_link.rb

@@ -0,0 +1,4 @@
+class FinancialLink < ActiveRecord::Base
+  has_many :financial_transactions
+  has_many :invoices
+end

app/models/financial_transaction.rb

@@ -3,6 +3,7 @@
 class FinancialTransaction < ActiveRecord::Base
   belongs_to :ordergroup
   belongs_to :user
+  belongs_to :financial_link
 
   validates_presence_of :amount, :note, :user_id, :ordergroup_id
   validates_numericality_of :amount, greater_then: -100_000,

app/models/invoice.rb

@@ -3,6 +3,7 @@ class Invoice < ActiveRecord::Base
 
   belongs_to :supplier
   belongs_to :created_by, :class_name => 'User', :foreign_key => 'created_by_user_id'
+  belongs_to :financial_link
   has_many :deliveries
   has_many :orders