Issue #602182 by Dave Reid, John Morahan: Fixed updatedb should clear cache.
Another drush_log() change.
Change drush_print() to drush_log() in role+perm commands.
Issue #1785060 by Owen Barton: drush site-set autocomplete is not complete
Fix complete.inc spacing.
Issue #1785072 by Owen Barton: when site is set, autocomplete doesn't work identical to when using the alias directly
Add static cache to autocomplete, to avoid cache misses when detected site/root change after bootstrap.