v1.3.0

Added

• V remove(K key) - removes an entry and returns its live value (or null
  if absent/expired). Not counted as a hit or miss.
• V computeIfAbsent(K key, Function<? super K, ? extends V> loader) and an
  overload taking an explicit long ttlMillis - returns the cached value or
  computes, stores and returns it. Runs under the cache lock, so concurrent
  callers for the same key run the loader once. Counts as one hit or miss. A
  null result or an exception stores nothing.
• List<K> keys() - snapshot of live keys, least- to most-recently-used, with
  no effect on recency or statistics.