Implement `Serialize` instance for `Text`

[Adithya Kumar]

This includes both Strict.Text and Lazy.Text

• Implement Serialize (Strict.Text)
• Implement Serialize (Lazy.Text)
• Add roundtripping tests
• Add benchmarks

[Adithya Kumar]

Note that we need to implement the instances differently for text < 2 and text >= 2. Use CPP macros to control the implementation accordingly.

[Adithya Kumar]

See #9 and #11