Add FastCraft plugin - #475

It's probably best to wait until I add a toggle command before adding this to the server, so that players can disable it for themselves if they don't want to use it.

This is like, modifying stuff that you might actually want to test on a testing server, hence the test result might be different without using your plugin... making it harder to trouble shoot.
I don't see what kind of "addition" this will give xd

Normal crafting is still accessible through a button In FastCraft, it's completely untouched by FastCraft, so interfering with troubleshooting shouldn't be an issue. And I've actually uncovered some bugs in CraftBukkit by using FastCraft (SPIGOT-5534, SPIGOT-5642), so there could be some utility to having this on a test server.

Updated so that players are able to enable/disable FastCraft for themselves :)