Feature: Added a Tax Management form and a beer consumption report.

Chore: Fixed some Form_Load function names as they were copied from old forms and were not neat.
Feature: Management BI Improved and should be pretty much solid by now.

Tanshu.Accounts.PointOfSale/Masters/TaxEditForm.cs

@@ -0,0 +1,81 @@
+using System;
+using System.Windows.Forms;
+using Tanshu.Accounts.Repository;
+using Tanshu.Accounts.Entities;
+using System.Linq;
+using System.Collections.Generic;
+using System.Text.RegularExpressions;
+
+namespace Tanshu.Accounts.PointOfSale
+{
+    public partial class TaxEditForm : Form
+    {
+        private Guid? _taxID;
+        public TaxEditForm(Guid taxID)
+            : this()
+        {
+            _taxID = taxID;
+        }
+
+        public TaxEditForm()
+        {
+            InitializeComponent();
+        }
+
+        private void TaxEditForm_Load(object sender, EventArgs e)
+        {
+            Tax tax;
+            if (_taxID.HasValue)
+            {
+                using (var bi = new TaxBI())
+                {
+                    tax = bi.Get(x => x.TaxID == _taxID.Value);
+                    txtName.Text = tax.Name;
+                    txtRate.Text = (tax.Rate * 100).ToString();
+                }
+            }
+            txtName.Focus();
+        }
+
+        private void btnCancel_Click(object sender, EventArgs e)
+        {
+            this.Close();
+        }
+
+        private void btnOk_Click(object sender, EventArgs e)
+        {
+            Tax tax;
+            using (var bi = new TaxBI())
+            {
+                if (_taxID.HasValue)
+                    tax = bi.Get(x => x.TaxID == _taxID.Value);
+                else
+                    tax = new Tax();
+
+                if (string.IsNullOrEmpty(txtName.Text.Trim()))
+                    return;
+                tax.Name = txtName.Text.Trim();
+
+                if (string.IsNullOrEmpty(txtRate.Text.Trim()))
+                    txtRate.Text = "0";
+                decimal rate;
+                if (!decimal.TryParse(txtRate.Text, out rate) || (rate < 0 || rate > 100))
+                {
+                    MessageBox.Show("Tax Rate is not valid, it must be between 0 to 100 percent.");
+                    txtRate.Focus();
+                    return;
+                }
+                else 
+                    tax.Rate = rate / 100;
+
+                if (_taxID.HasValue)
+                    bi.Update(tax);
+                else
+                    bi.Insert(tax);
+                bi.SaveChanges();
+            }
+            MessageBox.Show("Update / Save Successful");
+            this.Close();
+        }
+    }
+}