buildroot

nodm: new package

[Peter: propagate linux-pam dependencies/comment,
	needs wordexp.h, not available on uClibc,
	use /etc/default/nodm for config override,
	correct github/site/source handling,
	disable help2man]
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>