Since we now over-write the wally malloc/free functions, we need to do
so for tests as well. Here we pull up all of the common setup/teardown
logic into a separate place, and update the tests that use libwally to
use the new common_setup core
Changelog-None
Now that we have json_stream in common/, we can move all the related
helpers from lightningd/json to common/json. This way everyone can
benefit of them (including libplugin, the plugins themselves,
potentially lightning-cli), not lightningd alone!
Note that the Makefile of the common/test/ had to be modified, because
the new helpers make use of common/wireaddr... Which turns out to
\#include <lightingd/lightningd.h> ! So we couldnt just include the .c
and add mocks if we redefined some structs (hello run-param).