Do not chmod +s chvt: instead, rely on sudo

The SUID flag may be lost on update, and relying on sudo is
slightly more secure.

We create a file in /etc/sudoers.d/ : these files are sourced by
default since sudo 1.7.2p1-1 (Ubuntu 10.04 lucid, Debian squeeze).

Fixes #723.
*/releases: Specify if a release should be tested or not

Each release line is now in the following format:
`release[*][|other,key,words]`

 - * indicates that the release is unsupported
 - keywords are comma-separated, and can currently be `test` or
   `notest`. Default is for supported releases to be tested (can
   be overridden with `notest`), and unsupported ones not to be
   tested (can be overridden with `test`).
installer: Fix accidental prefix match.
enter-chroot: Remap devbroker-access group.

Enables security key users to add themselves to the group, and/or
add custom udev rules.
Merge pull request #1177 from drinkcat/remap-devbroker-access

enter-chroot: Remap devbroker-access group.
Merge pull request #1140 from drinkcat/releases-flags

*/releases: Specify if a release should be tested or not
Merge pull request #727 from drinkcat/sudo-chvt

Do not chmod +s chvt: instead, rely on sudo
Makefile: compile with -Os as well

Good to spot strange bugs that only appear with certain flags.
targets/common, compile: Insert include files as needed.
Support croutoncycle commands via websocket
Add basic chroot listing and switching to the extension

TODO: croutoncycle should check version and then write 'C' to the fifo.
Only show one of the windowlist or the "connected" status
Hide log behind checkbox, and move disable button.
Extension should still display "connected" with old chroots
Bigger font size.

But, seriously, we need some UI redesign.
websocket: Split file in 2 parts.

websocket.h with generic functions, websocket.c with specific parts.
websocket.h/popen2: Check command exit status.
fbserver: WebSocket server to serve X11 framebuffer content
croutonfindnacl: Helper script to find NaCl process and shm.
findres: Helper script to find best resolution.