Port to D8 !

Here's a patch that ports all the examples to Drupal 8. Not a big deal at this point, because D8 has very few differences from D7, but maintaining this port will be a continuous process until D8 is released. Right now, the only change is in the .info files, where core=7.x changes to core=8.x.

The only example that doesn't install in Drupal 8 is the Tokens Example module, because that relies on the Token module which doesn't have a D8 port yet.

All tests in all the other Example modules run green in D8 after this patch.

The examples should be of great help to people trying to write patches for D8. (And to get a bug fixed in D7, you *have* to patch D8 first!) There are very few D8 modules out there that people can use to demonstrate bugs and test patches. The D8 Examples modules should make it easier for people to contribute to Drupal core development.