0.8.4

[Ray Strode]

Hey guys,

I've been really slack about plymouth releases for a long while now,
and I so I cut one today.  At some point I want to do proper
documention, and get the fsck story figured out. When those things
happen, I'll go to 0.9.  In the mean time, here's 0.8.4.  Despite the
long time span since 0.8.3 there's nothing ground breaking or super
noteworthy for this release.  Some of the changes include:

- plymouth client hang fix
- support for different fonts in the label control
- updates to work with newer libpng
- set-default-theme quoting fixes
- better support for serial consoles
- support for 'ignore-keystroke' and 'hide-message' commands
- better integration with upstart and systemd
- fd leak fixes
- more configuration options for throbgress plugin
- drm renderer fixes
- terminal fixes
- x11 renderer fixes
- improved debug logging output
- support corner cases for animations better
- use /dev/fb0 instead of /dev/fb for framebuffer
- change how we do socket communciation between client and daemon
- add --kernel-command-line option to override /proc/cmdline
- miscellaneous other changes
- buildsystem fixes

--Ray