Provide a Tugboat template for Acquia hosted sites

[baluv3]

Splitting this ticket off of #96.

At the Tugboat BoF, people requested support for Tugboat OOTB when spinning up new sites and clients. There is a PR in progress, TugboatQA/images#102, that creates a template for Pantheon.

The activity this ticket is to create a similar template for Acquia.

The same sort of scaffolding for Tugboat that we're doing for Pantheon hosted sites we should be doing for Acquia sites.

• Tugboat configuration
• task commands
• downsync databases
• Matching PHP and Database versions
• Setting up memcache if project is configured to use it

[justafish]

This has pretty much been covered in #213, bar some explicit helper tools for fetching Acquia databases