Fix install path

Index: CMakeLists.txt
--- CMakeLists.txt.orig
+++ CMakeLists.txt
@@ -181,11 +181,11 @@ endif()
 
 
 install (TARGETS tea DESTINATION bin)
-install (FILES ${tea_ICONSVG} DESTINATION share/icons/hicolor/scalable/apps)
-install (FILES ${tea_ICONPNG32} DESTINATION share/icons/hicolor/32x32/apps)
-install (FILES ${tea_ICONPNG48} DESTINATION share/icons/hicolor/48x48/apps)
-install (FILES ${tea_ICONPNG64} DESTINATION share/icons/hicolor/64x64/apps)
-install (FILES ${tea_ICONPNG128} DESTINATION share/icons/hicolor/128x128/apps)
+install (FILES ${tea_ICONSVG} DESTINATION ${CMAKE_INSTALL_PREFIX}/share/icons/hicolor/scalable/apps)
+install (FILES ${tea_ICONPNG32} DESTINATION ${CMAKE_INSTALL_PREFIX}/share/icons/hicolor/32x32/apps)
+install (FILES ${tea_ICONPNG48} DESTINATION ${CMAKE_INSTALL_PREFIX}/share/icons/hicolor/48x48/apps)
+install (FILES ${tea_ICONPNG64} DESTINATION ${CMAKE_INSTALL_PREFIX}/share/icons/hicolor/64x64/apps)
+install (FILES ${tea_ICONPNG128} DESTINATION ${CMAKE_INSTALL_PREFIX}/share/icons/hicolor/128x128/apps)
 
-install (FILES ${tea_DESKTOP} DESTINATION share/applications)
+install (FILES ${tea_DESKTOP} DESTINATION ${CMAKE_INSTALL_PREFIX}/share/applications)
 
