Log Message:
net/ruby-connection_pool: update to 2.2.3

Update ruby-connection_pool to 2.2.3.

2.2.3
------

- Pool now throws `ConnectionPool::TimeoutError` on timeout. [#130]
- Use monotonic clock present in all modern Rubies [Tero Tasanen, #109]
- Remove code hacks necessary for JRuby 1.7
- Expose wrapped pool from ConnectionPool::Wrapper [Thomas Lecavelier, #113]