fix RewritePlugin initialization

Error was introduced in 6d68a48
Merge pull request #73 from jhawthorn/rewrite_fix

fix RewritePlugin initialization
importfeeds migration: remove prefix (GC-503)
merge
fix the expanduser of the importfeeds dir configuration
importfeeds: add relative_to config
importfeeds: document the relative_to configuration option
Merge pull request #74 from phmongeau/relative_feeds

relative importfeeds m3u path
cleanup, docs, and changelog for relative_to (#74)
add thanks to changelog note for #74
allow convert to be used without embedart enabled
document migration from 1.0 to 1.1