Add opcache, xsl and intl, share 3306 port of db container and adapt logs shipping for sf3

[PyRowMan]

Description

The main goal of my Pull Request is to improve the usability of this docker containers, you'll find diverse improvements in it.

Usage

There is nothing you have to change in your configuration

Changes

• Activating opcache in order to improve performances
• Since symfony 3 the logs folders have been moved, i've changed the place where they are loaded from for the ELK container
• The main db port have been shared in order to allow access to db from thrid party software
• Finally I've added some essentials php mods for symfony 3

Misc

These changes are related with this PR : #79