### Added

- Optional serde support for agb-hashmap and agb-fixnum via the `serde` feature flag. The flag is also exposed in the agb crate.
- Added `set_background_palette` to be able to set a single background palette.

### Changed

- Using neither of the testing and backtrace features will mean there is no panic handler.

### Fixed

- Fixed build error due to breaking change in `xmrs`.
- The backtrace feature works on ARM now.