restart by ctl+alt+bs

[James Cameron]

The Zap feature to kill X server.  It was disabled upstream.  Cascaded
to OLPC OS in in 11.3.0.  Raised as #11202 [1], as a regression, but
not resolved.

It can be easily restored [2], and some deployments have done that.

The other functions you desire can be implemented by replacing olpc-dm
with gdm, and removing olpc-switch-desktop.  See devel@ archives
around 17th March, subject "Boot Menu for XO" [3].

See also sugar-devel@ around 14th April, subject "Sugar 0.102 testing
images (34002)" for a discussion about an issue that appears when
using gdm [4].

References:

1.  http://dev.laptop.org/ticket/11202
2.  http://wiki.laptop.org/go/OS_Builder/Edit_a_config_file#Example_uses
3.  http://lists.laptop.org/pipermail/devel/2014-March/038231.html
4.  http://lists.sugarlabs.org/archive/sugar-devel/2014-April/047975.html

-- 
James Cameron
http://quozl.linux.org.au/