refs #909 Add null validations

ogWebconsole/src/app/components/groups/shared/organizational-units/edit-organizational-unit/edit-organizational-unit.component.ts

@@ -46,38 +46,38 @@ export class EditOrganizationalUnitComponent implements OnInit {
     this.isEditMode = !!data?.uuid;
 
     this.generalFormGroup = this._formBuilder.group({
-      name: ['', Validators.required],
-      parent: [''],
-      description: [''],
-      type: ['', Validators.required]
+      name: [null],
+      parent: [null],
+      description: [null],
+      type: [null]
     });
 
     this.additionalInfoFormGroup = this._formBuilder.group({
-      comments: [''],
+      comments: [null],
     });
 
     this.networkSettingsFormGroup = this._formBuilder.group({
-      proxy: [''],
-      dns: [''],
-      netmask: [''],
-      router: [''],
-      ntp: [''],
-      p2pMode: [''],
-      p2pTime: [0, Validators.min(0)],
-      mcastIp: [''],
-      mcastSpeed: [0, Validators.min(0)],
-      mcastPort: [0, Validators.min(0)],
-      mcastMode: [''],
+      proxy: [null],
+      dns: [null],
+      netmask: [null],
+      router: [null],
+      ntp: [null],
+      p2pMode: [null],
+      p2pTime: [null],
+      mcastIp: [null],
+      mcastSpeed: [null],
+      mcastPort: [null],
+      mcastMode: [null],
       menu: [null],
       hardwareProfile: [null],
       validation: [false]
     });
 
     this.classroomInfoFormGroup = this._formBuilder.group({
-      location: [''],
+      location: [null],
       projector: [false],
       board: [false],
-      capacity: [0, Validators.min(0)],
+      capacity: [null],
       remoteCalendar: [null]
     });