Add failing test ahowing refs are not currently right.
Add another test, rename a var.
For all PHP adapters for which it makes sense, wrap a reference always.
Make dedicated wrapper for PHP classes.

Means that W_PHPGenericAdapter can consistently wrap a reference and
I can assert this.
Some renamings and assertions.

To make it more clear where something should be a reference.
Move refrence creation outside of W_PHPRef and assert we always get a ref.
Add a missing deref() and rename some vars for clarity.
xpassing test.