PoW: migrate to shared memory feature of Node 9/Node 10

As explained in #689 (closed), and after the problems with #1234 (closed) and #1256 (closed), this is definitely our target.

Yet, this requires us to migrate to Node 9 or Node 10.

mentioned in issue #1256 (closed)

I've made some changes in the code and built a Linux release with NodeJS 9.4.0 + NwJS 0.28.0. So far, the migration to NodeJS 9 just works :-)

I need to make the same test with ARM and Windows.

I lost my 2 last nights, but finally it also works on Windows.

I've tested on ARM as well, no problem.

Now I just need to modify the PoW to use the memory sharing API.

Note: for Windows, it seems to work only with NodeJS 9.1.0 and NwJS 0.26.5. Newer versions just bug: but I don't know if the problem comes from NodeJS > 9.1 or NwJS > 0.26.5.

I'm trying to use newer versions, I will see what is the best.

Apperently, the Windows bug with Windows comes from NwJS 0.28.0: https://github.com/nwjs/nw.js/issues/6390

So for now I will develop the feature with NodeJS 9.1.0 + NwJS 0.27.1, but I hope NwJS 0.28.1 will be released for Duniter 1.7.0 and that we can switch to this newer version.

mentioned in issue #1270 (closed)

changed milestone to %1.9

No more object, as Duniter's PoW will is being oxide.

closed