Trap TERM signal. Without this, bash still executes the EXIT handler upon receiving TERM, but dash doesn't.
Fixes to croutonclip. Proper traps, limit usage of temporary files, detect aura window id.
Minor fixes to croutonurlhandler.
Major simplification of the logic in croutonxinitrc-wrapper.
Simpler croutonclip detection in xinit.
Improvements to Chromium extension.
Fixes in websocket.c:
 - Split socket_server_accept in 2 chunks.
 - Improved popen2, uses poll/waitpid to check if there is more data
   to read, and if the child process exited.
 - Clean up error messages.
 - Improve comments and formatting.
 - Verify the validity of base64 output.
Pull in xclip package dependency in extension, improve comments.
Rename cros-extension to extension.