v0.4.1

This version brings support for Solidity versions 0.8.0-0.8.3. Namely:

1. Add support for unchecked blocks
2. Ensure that when wrapping unchecked state variable updates, an updated block is emitted in the wrapper
3. Make sure that all Scribble arithmetic is unchecked. When designing scribble we aim to minimize the set of possible exceptions coming from Scribble instrumentation. The tradeoff here is that users need to think more carefully when writing arithmetic in Scribble as its unchecked.