adding more screenshots and updating captions

webApps/apps.json

@@ -387,19 +387,27 @@
       "screenshots": [
         {
           "url": "https://raw.githubusercontent.com/owncloud/awesome-ocis/main/webApps/owncloud/web-app-dicom-viewer/screenshots/1.png",
-          "caption": "Preview a DICOM file and it's most important meta data"
+          "caption": "Preview a DICOM image and it's most important meta data."
         },
         {
           "url": "https://raw.githubusercontent.com/owncloud/awesome-ocis/main/webApps/owncloud/web-app-dicom-viewer/screenshots/2.png",
-          "caption": "Display all corresponding metadata in sidebar"
+          "caption": "The extension allows to zoom, rotate and flip the preview of the DICOM image."
         },
         {
-          "url": "https://raw.githubusercontent.com/owncloud/awesome-ocis/main/webApps/owncloud/web-app-dicom-viewer/screenshots/2.png",
-          "caption": "Preview a DICOM file and it's most important meta data on a mobile device"
+          "url": "https://raw.githubusercontent.com/owncloud/awesome-ocis/main/webApps/owncloud/web-app-dicom-viewer/screenshots/3.png",
+          "caption": "Inverting the colors of the preview of the DICOM image is also supported."
         },
         {
-          "url": "https://raw.githubusercontent.com/owncloud/awesome-ocis/main/webApps/owncloud/web-app-dicom-viewer/screenshots/2.png",
-          "caption": "Display all corresponding metadata on a mobile device"
+          "url": "https://raw.githubusercontent.com/owncloud/awesome-ocis/main/webApps/owncloud/web-app-dicom-viewer/screenshots/4.png",
+          "caption": "Display all corresponding metadata in sidebar."
+        },
+        {
+          "url": "https://raw.githubusercontent.com/owncloud/awesome-ocis/main/webApps/owncloud/web-app-dicom-viewer/screenshots/5.png",
+          "caption": "Preview a DICOM image and it's most important meta data on a mobile device."
+        },
+        {
+          "url": "https://raw.githubusercontent.com/owncloud/awesome-ocis/main/webApps/owncloud/web-app-dicom-viewer/screenshots/6.png",
+          "caption": "Display all corresponding metadata on a mobile device."
         }
       ],
       "resources": [