Please update Proguard section

[igozhenko]

I got some problem with Proguard.

Information from Readme is not correct for 1st line,

-dontwarn com.cocosw.favor.** { ; } -keep class com.cocosw.favor.* { *; }

Also preferences was not create and stored until I have added information about to keep my interface with @Flavor too

-dontwarn com.cocosw.favor.** 
-keep class com.cocosw.favor.** { *; }
-keep interface {your.package}.{YourInterface} {
  <methods>;
}