0.9.0

This release:

- Use udev for graphics device enumeration
- Add new text plugin to replace the tribar one
- Add background tiling and watermark support to two-step
- Make various plymouth commands that change state be resilient to being
  called multiple times
- Support going back to the initrd at shutdown
- Keyfile parser improvements
- Make plymouthd use better defaults when running on top of X11
- Fixes for systems using QXL
- minor two-step plugin fixes
- Use /sys/class/tty/console/active instead of parsing /proc/cmdline for consoles
- Documentation improvements
- Drop driver specific renderers and use generic driver across the board
- Better debug message output
- systemd integration fixes
- upstart integration fixes
- initrd scripts fixes
- Misc fixes