- Adds --output to import, export, rehead, and concat.
- Adds "concat" subcommand to sav --help
- Allows for concat with single VCF input file.
- Fixes assert in dot_slow().
- Fixes header incompatibility bug during concat.
- Fixes sample subsets of sparse FORMAT fields.
- Validates FORMAT field sizes before writing.
- Fix for TBI indices containing multiple contigs.
- Updates packaging to use musl.