We now hand around struct json_out members, rather than using formatted
strings, so plugins need to construct them properly.
There's no automatic conversion between ' and " any more, so those
are eliminated too. pay still uses some manual construction of elements.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
1. Allow timers to be freed in their callback.
2. Clarify in header that we have to terminate our timer with timer_finished()
eventually.
3. We don't currently have plugins with more than one outstanding timer, but
it certainly would be possible, so fix in_timer to be a counter.
Suggested-by: @ZmnSCPxj
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
