Billing: Add possibility to automatically add business shares

Elwig/Helpers/AppDbContext.cs

@@ -44,6 +44,7 @@ namespace Elwig.Helpers {
         public DbSet<Member> Members { get; private set; }
         public DbSet<BillingAddr> BillingAddresses { get; private set; }
         public DbSet<MemberTelNr> MemberTelephoneNrs { get; private set; }
+        public DbSet<MemberHistory> MemberHistory { get; private set; }
         public DbSet<AreaCom> AreaCommitments { get; private set; }
         public DbSet<Season> Seasons { get; private set; }
         public DbSet<Modifier> Modifiers { get; private set; }