Program type already present: org.intellij.lang.annotations.JdkConstants$PatternFlags

Upgrading Timber from `4.7.0` to `4.7.1` in a library of mine, causes another app using that library to fail building with this error.

```
AGPBI: {"kind":"error","text":"Program type already present: org.intellij.lang.annotations.JdkConstants$PatternFlags","sources":[{}],"tool":"D8"}
```

This can be fixed by including in my `build.gradle`

```groovy
configurations {
cleanedAnnotations
compile.exclude group: 'org.jetbrains' , module:'annotations'
}
```

Might be related to #327

Start with the dependency configuration shown in build.gradle and compare Timber 4.7.0 with 4.7.1. Reproduce the D8 duplicate-class error, inspect the resolved org.jetbrains annotations dependencies, and review related issue #327. Done means consumers no longer need the manual exclusion to build successfully.

Written by the indexing model from the issue text.