remove shadow effects from places icons, reduce size

core/img/places/calendar-dark.png

core/img/places/calendar-dark.svg

core/img/places/contacts-dark.png

core/img/places/contacts-dark.svg

core/img/places/file.png

core/img/places/file.svg

core/img/places/files.png

core/img/places/files.svg

core/img/places/folder.png

core/img/places/folder.svg

core/img/places/home.png

core/img/places/home.svg

core/img/places/link.png

core/img/places/music.png

core/img/places/music.svg