Adjust spaces and empty lines in Dockerfile

Details:

- Remove trailing spaces
- Remove additional empty lines
- Replace a few tabs with spces for consistent indent

Dockerfile

@@ -28,10 +28,8 @@
 #
 #       docker run --device /dev/kvm --device /dev/snd -v /tmp/.X11-unix:/tmp/.X11-unix -e "DISPLAY=${DISPLAY:-:0.0}" sickcodes/docker-osx:latest
 #
-#
 # Run with SSH:
 #
-# 
 #       docker run --device /dev/kvm --device /dev/snd -e RAM=6 -p 50922:10022 -v /tmp/.X11-unix:/tmp/.X11-unix -e "DISPLAY=${DISPLAY:-:0.0}" sickcodes/docker-osx:latest
 #       # ssh fullname@localhost -p 50922
 #
@@ -49,7 +47,6 @@
 #
 #       docker run ... -e EXTRA="-usb -device usb-host,hostbus=1,hostaddr=8" ...
 #       # you will also need to pass the device to the container
-#
 
 FROM archlinux:latest