Method ambiguity when LAMBDA is used

[wysohn]

When LAMBDA expression is used, and there is an overloaded method where both the original and the overloaded method accepts the functional interface, then it cannot distinguish which one to use.

For example,

runTask(Plugin plugin, Runnable task)

and

runTask(Plugin plugin, Consumer<BukkitTask> task)

is overloaded method, and both Runnable and Consumer are functional interface. For now, I believe TRG always choose the first method if there are more than one method with the similar signature.

[wysohn]

This requires re-structuring how the parser is parsing the IDs