Adding album artist fix
Show album artist stats

See #855
Stats only count albums in the database

Items might have the `album` field set without belonging to an album in
the beets database. We only count the albums that are represented in
the database.
Refactor model formatting

Remove all formatting related code from models. It now lives in the
`FormattedMapping` class. Only API change is from `model.formatted` to
`model.formatted()`.
Item fields take precedence over Album fields in formatting

For consistency, this is reversed when formatting paths. Fixes #858.
Merge pull request #917 from geigerzaehler/stats

Improvements for stats command
Changelog for #917/#855
Changelog for #878
Merge pull request #918 from geigerzaehler/formatting

Model formatting: Refactor and fix precedence
Changelog for #858/#918
Works faster then checking each result item with isinstance
Merge pull request #920 from andriykohut/master

With new discogs api there is no need for filtering releases with isinstance
Move albums_in_dir() from autotag to import module

Has nothing to do with the former
Tags are not read while walking the import tree.

This makes skipping directories on incremental imports much faster and
fixes #158.
PEP8 fixes
Formatted mapping uses field type to determine default
Changelog for #158
New api requires client and dict as parameters for Release initialization
Merge branch 'master' of github.com:sampsyo/beets
info: Specify files through library query