New service for logging statistics of all jdbc queries

## Context 
We needed to log statistics of all jdbc queries.

## Description
- In `*Spy` classes, each call to `System.currentTimeMillis()` has been replaced by a call to `TimeSource.getTime()`
- New features added to the `JdbcManager` class :
    * connection factories management (implementations of the `ConnectionFactory` interface)
    * connection pool listeners management (implementations of the `ConnectionPoolListener` interface)
- `.gitignore` file completed to filter log files