add form to create employee

Reviewed-on: #18
Reviewed-by: Get in my car i have candy <huydw@proton.me>

src/app/employee/Employee.ts

@@ -1,10 +1,15 @@
+import {Qualification} from "../Qualification";
+
 export class Employee {
-  constructor(public id?: number,
-              public lastName?: string,
-              public firstName?: string,
-              public street?: string,
-              public postcode?: string,
-              public city?: string,
-              public phone?: string) {
+  constructor(
+    public id?: number,
+    public lastName?: string,
+    public firstName?: string,
+    public street?: string,
+    public postcode?: string,
+    public city?: string,
+    public phone?: string,
+    public skillSet?: Qualification[]
+  ) {
   }
 }