Log Message:
Add p5-CHI.

CHI provides a unified caching API, designed to assist a developer
in persisting data for a specified period of time.

The CHI interface is implemented by driver classes that support
fetching, storing and clearing of data. Driver classes exist or
will exist for the gamut of storage backends available to Perl,
such as memory, plain files, memory mapped files, memcached, and
DBI.

CHI is intended as an evolution of DeWitt Clinton's Cache::Cache
package, adhering to the basic Cache API but adding new features
and addressing limitations in the Cache::Cache implementation.

* Easy to create new drivers
* Uniform support for namespaces
* Automatic serialization of keys and values
* Multilevel caches
* Probabilistic expiration and busy locks, to reduce cache miss stampedes
* Optional logging and statistics collection of cache activity