Weekly pre-release

New Features:

• Fast 8bit codepath
• Shell auto-completion support
• Add a --skip option

Bugfixes:

• Depend on a y4m version that properly supports odd-dimensioned content
• Fix and enable directional intra prediction modes

API Changes:

• Add an explicit thread field in the Configuration to manage the threadpool using the API
• Cap the default threadpool to 4 maximum threads
• Default the tuning to psy
• Remove the explicit lookahead logic from the API