chore: prepare v1.6.0

[braddunbar]

1.6.0 (March 22, 2024)

Added

• Add Bytes::is_unique (add Bytes::is_unique #643)

Documented

• Fix changelog typo (doc: fix changelog typo #628)
• Fix some spelling mistakes ([ISSUE #632]docs: fix some spelling mistakes #633)
• Typo fix (docs: typo fix #637)
• Fix broken links (docs: fix broken links #639)
• Add security policy (readme: add security policy #649)

Internal changes

• Move comment to correct constant (Move comment to correct constant #629)
• Various cleanup (Various cleanup #635)
• Simplify UninitSlice::as_uninit_slice_mut() logic (uninit_slice: simplify as_uninit_slice_mut() logic #644)
• Use self. instead of Self:: (Self:: -> self. #642)
• BytesMut: Assert alignment of Shared (BytesMut: Assert alignment of Shared #652)
• Remove unnecessary namespace qualifier (Remove some unnecessary namespaces #660)
• Remove an unnecessary else branch (Remove an unnecessary else #662)
• Remove unreachable else branch (Remove unreachable else #661)
• make parameter mut in From<Vec> (Mut parameter #667)
• Restore commented tests (Restore commented tests #665)
• Use sub instead of offset (Use sub instead of offset #668)
• Calculate original capacity only if necessary (Calculate original capacity only if necessary #666)
• set_vec_pos does not need a second parameter (set_vec_pos does not need a second parameter #672)
• get_vec_pos: use &self instead of &mut self (get_vec_pos: use &self instead of &mut self #670)
• Refactor split_at/split_to (Refactor split_at/split_to #663)
• Use Iterator from the prelude (Use Iterator from the prelude #673)
• copy_to_bytes: Add panic section to docs (copy_to_bytes: Add panic section to docs #676)
• Remove redundant reserve call (Remove redundant reserve call #674)
• Use ManuallyDrop instead of mem::forget (Use ManuallyDrop instead of mem::forget #675)

[Darksonn]

Thanks.