简化findViewById使用butterknife与android-butterknife-zelezny

使用资源：

https://github.com/JakeWharton/butterknife

https://github.com/avast/android-butterknife-zelezny

一个轻量级的本地数据存储库：

https://github.com/anupcowkur/Reservoir

butterknife使用注意事项：

butterknife在代码混淆的时候，需要添加如下代码，否则空指针

-dontwarn butterknife.**
-keep class butterknife.**{*;}
-keep class **$$ViewBinder { *; }
-keepclasseswithmembernames class * {
    @butterknife.* <fields>;
}
-keepclasseswithmembernames class * {
    @butterknife.* <methods>;
}