Merge pull request 'Update calc icon' (#206) from tobtoht/feather:calc_icon into master

Reviewed-on: feather/feather#206

src/assets.qrc

@@ -38,6 +38,7 @@
     <file>assets/images/file.png</file>
     <file>assets/images/ghost.png</file>
     <file>assets/images/ghost_icon.png</file>
+    <file>assets/images/gnome-calc.png</file>
     <file>assets/images/history.png</file>
     <file>assets/images/info.png</file>
     <file>assets/images/key.png</file>

src/mainwindow.ui

@@ -261,7 +261,7 @@
       <widget class="QWidget" name="tabCalc">
        <attribute name="icon">
         <iconset resource="assets.qrc">
-         <normaloff>:/assets/images/coldcard.png</normaloff>:/assets/images/coldcard.png</iconset>
+         <normaloff>:/assets/images/gnome-calc.png</normaloff>:/assets/images/gnome-calc.png</iconset>
        </attribute>
        <attribute name="title">
         <string>Calc</string>