Add a VVV specific configuration for phpMyAdmin

Allows us to specify that dropping databases is ok. This would normally be an undesirable thing, but our requirements are a bit different when running it locally in a VM.

This also sets us up to configure phpMyAdmin in other ways.

Closes #216
Merge pull request #218 from 10up/216-enable-drop-database

Add a VVV specific configuration for phpMyAdmin
Slight tweaks to the 'Purpose' statement to stress core objectives
Update text in VVV as a MAMP replacement area
Remove provision-pre and provision-post hints in README

It'd be great if we could deprecate these over time now that we have a better method in the auto site setup.
Update the Getting Started instructions to flow better with current requirements
Update expectations in What Did That Do
Refresh the Now What section

Removes some of the language around database persistence and auto importing of SQL as the hope is to deprecate some of this included functionality in the future and shift the responsibility to the auto site setup.

Adds a caveats section
Update Need Help section
Move some context area content up to Need Help
Update context area links
Consistent slash use on URLs...

...saving the world from unnecessary redirects, one at a time.
Use .x for packages that change minor releases often
Update phpMyAdmin version in README to 4.0.10
Update phpMyAdmin to 4.0.10
Another round of VirtualBox capital_B_dangit
Add link to wiki for auto site setup item
Expand on new vagrant up behavior
Add note about shell style guide usage
Add other improvements from the 1.0 cycle to CHANGELOG