[logback-user] DuplicateMessageFilter : time based duplication

Hi, We are using a modified version of ch.qos.logback.classic.turbo.DuplicateMessageFilter in our project. We replaced the LRUMessageCache with a cache with a time based eviction. This new cache is build with guava CacheBuilder. The goal is to avoid duplicate messages during a time frame. I joined the class as it may be useful to other Thanks Nicolas