This causes hierarchy to be runelite-client -> runelite-api and
injected-client -> runescape-api -> runelite-api. The mixin injector
fufills the runelite-api interface with access to the runescape-api
interfaces. The mixins live in runelite-mixins and are not loaded within
the client.
Note the obfuscated client classes do not pass JVM verification on 7+,
so the mixins are currently set to target Java 6.