Cache Head/Tail in events FsStore

Since the head and tail are sequences, and sequences can only
increase, it is possible to speed up certain comparisons
by caching the last known value of the sequence.

Change-Id: I16e035152cc23442c9c559ab684359501934ceaf
3 files changed
tree: 50fecc15ef18397c2094745b8ee3785e3560f4b7
  1. src/
  2. test/
  3. .gitignore
  4. pom.xml