* don't enforce async calls for thread-safe listeners (closes#1551)
* cleanups, remove structure compiling
* improve cloning a bit
* fix small issue in no-op structure modifier
* remove last usages of FieldUtils
* improve and fix equality check in container test
Note that things may not initially work as expected. There are known issues (see #880) relating to dimensions, chat packets, and tile entities. There were also internal changes to attributes, though hopefully those are fixed. As always, report issues on GitHub.
