用于理解RxJava而做的一个简易的EasyRxJava。
代码里给出了不同难易程度的EasyRxJava，easy1最简单，数字越大越难。（自己也在不断学习理解，不断更新中）
可以参考文章：https://www.jianshu.com/p/88aacbed8aa5
Copyright 2018 LVinnie
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