* Cache last commit to accelerate the repository directory page visit
* Default use default cache configuration
* add tests for last commit cache
* Simplify last commit cache
* Revert Enabled back
* Change the last commit cache default ttl to 8760h
* Fix test
* Add commit count caching
* Small refactoring
* Add different key prefix for refs and commits
* Add configuratuion option to allow to change caching time or disable it