Add generic name to the desktop files

krita/gemini/kritagemini.desktop

 [Desktop Entry]
 Version=1.0
 Type=Application
+GenericName=Digital Painting
 Name=Krita Gemini
 Name[ca]=Krita Gemini
 Name[de]=Krita Gemini
@@ -13,6 +14,6 @@ Name[sv]=Krita Gemini
 Name[uk]=Krita Gemini
 Name[x-test]=xxKrita Geminixx
 Exec=kritagemini
-Icon=kritagemini
+Icon=calligrakrita
 MimeType=application/x-krita;
 Categories=Qt;KDE;Graphics;

krita/sketch/kritasketch.desktop

@@ -12,7 +12,8 @@ Name[sk]=Krita Sketch
 Name[sv]=Krita Sketch
 Name[uk]=Krita Sketch
 Name[x-test]=xxKrita Sketchxx
+GenericName=Digital Painting
 Exec=kritasketch
-Icon=krita
+Icon=calligrakrita
 MimeType=application/x-krita;
 Categories=Qt;KDE;Graphics;