[ccan] CCAN update for 2015-10

[Rusty Russell]

Hi!

        I spend four hours on optimizing memeqzero, as you can see from
my blog post at http://rusty.ozlabs.org/?p=560 
        
	
Module of the Month: tcon (CC0)
==============================
tcon is a subtle module for other modules to create type canaries: eg,
ccan/tlist has a TLIST_TYPE(name, type) which declares a list which
holds "type".  tcon provides TCON_WRAP() helpers to add a canary to a
declaration tcon_unwrap() to access it, and tcon_check() to warns if an
expression isn't the same type as the canary.

In addition, canaries can now encode positive compile-time values using
TCON_VALUE, which can be accessed using tcon_value.

New modules:
============
        lpq: simple priority queue (David Gibson)

Minor updates & bugfixes:
========================
        isaac: info formatting fixes (Paul Wayper)
        lqueue/lstack: use ccan/tcon (David Gibson)
	mem: new routine memiszero
        opt: don't use malloc for errors if they set opt_allocator.
        order: total_order_cmp helper (David Gibson)
        ptrint: CONST_FUNCTION annotation (David Gibson)
        tal/str: fix for tal_strndup() of non-nul terminated strings
        tcon: make it useful in more situations (David Gibson)

Cheers,
Rusty.