Netnode graph tags

Detailed Description

Tag values to store graph info.

Macros
#define	NSUP_GR_INFO   'g'
	group node info: color, ea, text
#define	NALT_GR_LAYX   'p'
	group layout ptrs, hash: md5 of 'belongs'
#define	NSUP_GR_LAYT   'l'
	group layouts, idx: layout pointer