Added minecraft 1.12 pre7 support

[stefandollase]

As opposed to my commit message in f878966

Minecraft 1.12-pre3 seems to contain malformed class files. Not only Amidst, but also standard Java decompilers cannot read them, e.g. chv.class.

This change allows Amidst to ignore these classes as long as all required classes are found.

the new snapshots do not contain malformed class files. The malformed class files simply contain lambda expressions which we were not able to recognize (just like the decompiler that I used).

This PR also adds support to read byte code that contains lambda expressions. However, it does not allow us to search for a class file by a given lambda expression.

[ghost]

http://i.imgur.com/nHS8w5x.jpg
Both v4.3 beta versions seem to have a problem with PCMCv1.11.2
Interestingly v1.11.2 came out on 16w51 NOT 17w06
I haven't checked any other versions.

[stefandollase]

Yes, you are right about this. Sadly, our recognition mechanism becomes more and more fuzzy, which was one of the reasons for #146. #331 should be a first step to adjust this mechanism, however it is not yet done.

See here for which versions are currently grouped together by the recognition mechanism (scroll to the right). The marked line is the version you are talking about.

However, for this version, it is really only an issue because it might confuse the user. Other than that, it has no consequences. We still use the correct biome generator. The recognised version for example affects which algorithm is used for the structure generation, like temples. Thus, since we did not adjust these algorithms for newer versions of the game, it won't currently make a difference which version was recognised (see here).