fragment 0.4.0

Easily prevent unnecessary build() calls in StatefulWidget and its subtrees.

[0.0.1]

• Initial release.

[0.0.2]

• Add Fragment widget.

[0.1.0]

• Make two APIs look similar.

[0.1.2]

• Update document.

[0.1.3]

• Forbid context access in fragment()
• Diff by overriding == in Fragment

[0.2.0]

• Update interface

[0.2.1]

• Update readme

[0.2.2]

• Always rebuilt fragments in hot reload
• Allow nested fragment() calls

[0.3.0]

• Provide previous value & keys to builder
• Make nested fragment() calls act like React's useMemo
• Remove named fragments support
• Rename parameter deps to keys

[0.3.1]

• Ensure keys in children fragments form a subset of their parent fragment's keys.

[0.4.0]

• Enable null-safety
• Remove Fragment widget.