Created a UserControl LabeledTextBox.
1. This UserControl has a Label and a TextBox together, situated in a TLP which autosizes.
2. Added InvoiceTLP to Invoice tab.
3. Made InvoiceTLP have 9 cells.
4. Will add LabeledTextBox to each cell.
5. Created properties for LabeledTextBox to be able to access the Label and TextBox text inside.