ftintitle: add 'auto' option
restoring ft_in_title implementation
register import hook only if needed
restore write argument for ft_in_title
move metadata management in command function
Add tests for #1029

The mbngs library does not like to be called with whitespace-only criteria.
Fix #1029: whitespace-only searches
Merge commit 'ca431b0' (part of #1033)

This is the part of PR #1033 that fixes #1020.
Minor fixes for #1033
Changelog/docs for #1033/#1020
Fix mock function restoration in test :(

An argument for using decorators, context managers and stuff so this is
impossible to mess up.
Merge pull request #1011 from Kraymer/ftintitle_auto

ftintitle: add 'auto' option
Changelog for #1011 (fix #841)
lyrics: Remove script tags (fix #1034)
Updating to master to form a new PR.