Now with important logging, channel passing and interface updates

• network: introduce Linklocal6 IPv6 address mode
• memory: consistently use XML rather than JSON for backward compat
• memory: allow domain 0 memory to be managed (i.e. auto-ballooned)
• all: fix an fd leak in the channel-passing functions
• all: add the ability to log directly to Syslog
• all: optionally search PATH for executables rather than hard-code paths