Realize node name in the database

We previously had a fairly universal concept of a node "name" through the
code, but it was only constructed in the application logic, not in
the database.

This means that various database level operations were simply impossible when
using the name, and that a complex set of deconstructions had to be used
through the codebase to deal with this.

Now, we simply have the column in the database, and use it.  This fixes that
non-uniform API, a win alone, but also paves the way for a future when users
can assign more meaningful names to nodes without violating the expectations
of the overall system.

Signed-off-by: Daniel Pittman <daniel@rimspace.net>