Arguments could be captured even when signature is unknown

Consider functools.lru_cache; this is a built-in, so signature is not available. However, we still get args and kwargs if we trace the call (as happens often when the decorator is used on a traced class). Currently in the absence of a signature parameters end up being []. I think it's worthwhile to record arguments anyway.

Requires applandinc/appmap#22

For all intents and purposes blocked by #126 -- in CPython native functions are, to my knowledge, the only case where a function signature cannot be obtained. While it might be possible to implement and even test this without that, but it would be pretty useless.

首先检查涉及 functools.lru_cache 的跟踪调用的参数捕获路径，然后检查 applandinc/appmap#22 中的依赖关系以及阻塞问题 #126。完成的标准是：即使没有可用的函数签名，也会记录 args 和 kwargs，而不是让 parameters 为空。