Get rid of deprecated metadata

[cx384]

This solves a part of #601

The deprecated metadata gets converted to a proper ItemStackMetaRef.
All keys stay the same except for:

• Cans that use can_level now, since they didn't store a serialized table in the metadata before.
• charge which is now technic:charge, since any item (also from other mods) may have a technic charge which can cause compatibility problems.

(For other keys e.g. mode, the key is special to the item and not universally used, which is not that problematic, I guess.)

There is now only one place left where metadata is used, the sorting function of techinc chests:

technic/technic_chests/register.lua

Lines 149 to 150 in 5826c2f

	local m = st:get_metadata()
	local k = string.format("%s %05d %s", n, w, m)

However, I'm unsure how this should be changed.
Getting the whole stack meta as a table and use the amount of keys or a serialized version to sort, may be an option, but I don't think it is justified performance-wise.

To do

This PR is a Ready for Review.

(Maybe change the techinc chests sorting function.)

How to test

1. Start a game with the old version and get some tools, charge them up, change their modes, fill up some cans.
2. Switch to the new version and see if the tools still work as expected.

I tested it, and didn't find any problem, but I'm not sure if I missed something.

Compatibility note

Other mods which directly accessed the item metadata of technic items will not work anymore.

[SmallJoker]

Looks good aside from that. Yet not tested.

[SmallJoker]

☑️ Battery box works. Charge gets migrated
☑️ Can level works and gets migrated
☑️ Chain saw works and gets migrated
Flashlight works but seems to be bugged (discharges too quickly), not a problem introduced by this PR.
☑️ Prospector works
☑️ Sonic screwdriver produces a way too loud sound. It's somewhat weird to use but works.
☑️ Vacuum cleaner works

I'll merge these changes in a week unless there are objections. This is a longer delay than what I usually do because it affects existing maps.