Fixed the absolute paths in the desktop file

The application icons now install into the system icon theme. This also
results in the system always picking the best available icon to display.

To make installing simpler (and to make the names more consistent) the
icon files were moved into the folders of their resolution.

Fixes #383

docs/tiled.desktop

@@ -1,9 +1,9 @@
 [Desktop Entry]
 Name=Tiled
 Comment=Tile map editor
-Exec=/usr/bin/tiled
+Exec=tiled
 Terminal=false
 Type=Application
-Icon=/usr/share/tiled/images/tiled-icon-32.png
+Icon=tiled
 Categories=Graphics;2DGraphics;
 X-Desktop-File-Install-Version=0.1

src/tiled/mainwindow.cpp

@@ -136,8 +136,8 @@ MainWindow::MainWindow(QWidget *parent, Qt::WindowFlags flags)
     QIcon redoIcon(QLatin1String(":images/16x16/edit-redo.png"));
     QIcon undoIcon(QLatin1String(":images/16x16/edit-undo.png"));
 
-    QIcon tiledIcon(QLatin1String(":images/tiled-icon-16.png"));
-    tiledIcon.addFile(QLatin1String(":images/tiled-icon-32.png"));
+    QIcon tiledIcon(QLatin1String(":images/16x16/tiled.png"));
+    tiledIcon.addFile(QLatin1String(":images/32x32/tiled.png"));
     setWindowIcon(tiledIcon);
 
     // Add larger icon versions for actions used in the tool bar

src/tiled/tiled.pro

@@ -274,9 +274,17 @@ FORMS += aboutdialog.ui \
     saveasimagedialog.ui\
     editterraindialog.ui
 
-images.path = $${PREFIX}/share/tiled/images
-images.files += images/tiled-icon-32.png
-INSTALLS += images
+icon32.path = $${PREFIX}/share/icons/hicolor/32x32/apps/
+icon32.files += images/32x32/tiled.png
+INSTALLS += icon32
+
+icon16.path = $${PREFIX}/share/icons/hicolor/16x16/apps/
+icon16.files += images/16x16/tiled.png
+INSTALLS += icon16
+
+iconscalable.path = $${PREFIX}/share/icons/hicolor/scalable/apps/
+iconscalable.files += images/scalable/tiled.svg
+INSTALLS += iconscalable
 
 desktopfile.path = $${PREFIX}/share/applications/
 desktopfile.files += ../../docs/tiled.desktop

src/tiled/tiled.qrc

@@ -1,8 +1,6 @@
 <RCC>
     <qresource prefix="/">
         <file>images/about-tiled-logo.png</file>
-        <file>images/tiled-icon-16.png</file>
-        <file>images/tiled-icon-32.png</file>
         <file>images/16x16/application-exit.png</file>
         <file>images/16x16/document-export.png</file>
         <file>images/16x16/document-import.png</file>
@@ -28,6 +26,7 @@
         <file>images/16x16/window-close.png</file>
         <file>images/16x16/stock-duplicate-16.png</file>
         <file>images/16x16/terrain.png</file>
+        <file>images/16x16/tiled.png</file>
         <file>images/16x16/zoom-in.png</file>
         <file>images/16x16/zoom-original.png</file>
         <file>images/16x16/zoom-out.png</file>
@@ -73,5 +72,6 @@
         <file>images/16x16/show_hide_others.png</file>
         <file>images/24x24/dice.png</file>
         <file>images/24x24/terrain-edit.png</file>
+        <file>images/32x32/tiled.png</file>
     </qresource>
 </RCC>