Rename alignment options for radio groups

Use 'horizontal' and 'vertical'. Which are better terms and also align 
with other element's values.

projects/common/models/radio-button-group-element.ts

@@ -4,7 +4,7 @@ import { initFontElement, initSurfaceElement } from '../util/unit-interface-init
 
 export class RadioButtonGroupElement extends InputElement implements FontElement, SurfaceUIElement {
   options: string[] = [];
-  alignment: 'row' | 'column' = 'column';
+  alignment: 'vertical' | 'horizontal' = 'vertical';
   strikeOtherOptions: boolean = false;
 
   fontColor: string = 'black';

projects/editor/src/app/unit-view/page-view/properties-panel/element-properties.component.html

@@ -108,7 +108,7 @@
           <mat-label>{{'propertiesPanel.alignment' | translate }}</mat-label>
           <mat-select [value]="combinedProperties.alignment"
                       (selectionChange)="updateModel('alignment', $event.value)">
-            <mat-option *ngFor="let option of ['row', 'column']"
+            <mat-option *ngFor="let option of ['horizontal', 'vertical']"
                         [value]="option">
               {{ 'propertiesPanel.' + option | translate }}
             </mat-option>

projects/editor/src/assets/i18n/de.json

@@ -71,8 +71,8 @@
     "requiredField": "Pflichtfeld",
     "requiredWarnMessage": "Warnmeldung",
     "options": "Optionen",
-    "alignmentRow": "horizontal",
-    "alignmentColumn": "vertikal",
+    "vertical": "vertikal",
+    "horizontal": "horizontal",
     "resizeEnabled": "größenverstellbar",
     "action": "Aktion",
     "previous": "Vorherige Unit",