Phase III

-   Added:
    -   AccountInterface
    -   CheckingAccount
    -   SavingsAccount
-   Converted Account to abstract class
-   All instance variables are validated via exception handling

.vscode/launch.json

@@ -0,0 +1,21 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "java",
+            "name": "Current File",
+            "request": "launch",
+            "mainClass": "${file}"
+        },
+        {
+            "type": "java",
+            "name": "BankAcctApp",
+            "request": "launch",
+            "mainClass": "bankAcctApp.BankAcctApp",
+            "projectName": "Bank Account App_b3cd1e26"
+        }
+    ]
+}