res: change icon names

s/start-here/deepin-launcher/
s/invalid-dock_app/application-x-desktop/

tower: https://tower.im/projects/8f19f0bf0e754f0b82ef2c24bc230973/todos/f59e9d99dbac420b877a8dd78b008f6f/

Change-Id: I84bb80ee4cdb26a60239bb24557437836eb42640