Memory management

[egg82]

After doing some profiling, several things have jumped out at me:

• JSONFile#readNode can consume a significant amount of memory all at the same time
  • This is due to needing to throw the entire file into StringBuilder before JsonNode can load it
  • Eventually these objects are GC'd, but testing on my own system shows peaks of up to ~1.2GB used
• With my testing, Fetcharr's resting state consumes ~400MB RAM
  • I see only ~200MB of that accounted for in the profiler but most of it is byte[] and String
  • For both of these classes, I keep seeing PluginManagerImpl#downloadPlugins come up with YamlConfigurationLoader#build as the culprit
  • That said, ZipFile seems to be a large portion of memory usage here