Determine entries after module-deps.

The row.file property is added by module-deps, which is ran after the
'record' pipeline event. On UNIX systems, it seemed to have worked in
the previous order, but on Windows our pipeline handler ran before
module-deps had the opportunity to add the field, causing path.resolve
issues later.

Change our hook listener to run at the end of the 'dups' event, and push
entry rows. We order and sort the entry rows in the flush handler,
before retrieving the 'file' property.
Spawn browserify in tests correctly on Windows.

On Windows, npm creates a batch wrapper around binaries to enable them
to run from the command prompt. This requires us to invoke to determine
the path to the browserify binary and invoke it as the "command"
argument to cmd.exe.

Obviously, we can spawn normally on UNIX systems, and our tests continue
to do so.