Added Discogs search plugin.
Added a -e option to random that makes the distribution even among artists
Preliminary support for "date added" fields

This isn't yet finished, it needs some input on how to organize the data, and actually where to implement the use of this data, but it already works in setting the date
Using time.time() to store the import time
Formatting the import time in the view and paths

Added the %format{} template function to output the time to any format supported by time.strftime()
Support for date/time fields
correcting identation
Merge pull request #264 from duailibe/master

Adding support for the "Date added field"
fix stray character and tweak whitespace
move time formatting to format_for_path

This is where field value transformations belong.
config option for time format string
remove a stray constant
simplify album-adding by marking itime as album

Since both albums and items have an itime field, I'm putting itime into
ALBUM_KEYS_ITEM. This simplifies a lot of handling code. It also will make the
item and album itimes synchronize at some points, which is probably fine -- I
can't see a major use case for maintaining separate added dates for an album
and its tracks.
itime (#264): name change

I changed the "itime" field to "added" and the %format function to %time.
docs/changelog for date added (#264)
FIELDS lists use real types instead of SQL strings

This should enable some useful simplifications down the road.
lyrics: fix encoding for Lyrics.com
lyrics: substitute more punctuation (fixes #270)
^C dumps a stack trace in verbose mode
Perform template field substitution on albums

- adds another traversal through all plugins' template_fields for each
  'evaluate_template' call.
- requires the following idiom (or equivalent):

    @Plugin.template_field(field')
    def _tmpl_field(album):
        """Return stuff.
        """
        if isinstance(album, Album):
            return stuff