Allow hex/octal/binary radix numeric literals

[Y-Nak]

What was wrong?

closes #333

How was it fixed?

1. Added common::numeric::Literal to abstract string represented numeric literals.
2. Consistently use BigInt for semantic analysis, this approach is the same as rustc does (it holds u128 for numeric integers).
3. Removed lexical_core because it doesn't provide from_str_radix like methods. And also, I think we don't need to check the details of IntErrorKind in almost all cases. This is because, looking at the definition of IntErrorKind in detail, IntErrorKind::Empty is the only error kind that we have to consider it an internal compiler error.

To-Do

We may need to reconsider the usage of BigInt, I think it would be better to use U256 because:

1. it provides more reliability than multiple-precision arithmetic.
2. it improves performance a little bit.

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• OPTIONAL: Update Spec if applicable
• Add entry to the release notes (may forgo for trivial changes)
• Clean up commit history

[codecov-commenter]

Codecov Report

Merging #410 (8513f75) into master (3d1a9da) will increase coverage by 0.03%.
The diff coverage is 94.91%.

@@            Coverage Diff             @@
##           master     #410      +/-   ##
==========================================
+ Coverage   86.20%   86.23%   +0.03%     
==========================================
  Files          67       68       +1     
  Lines        4110     4135      +25     
==========================================
+ Hits         3543     3566      +23     
- Misses        567      569       +2     

Impacted Files	Coverage Δ
compiler/src/yul/mappers/expressions.rs	88.67% <ø> (ø)
parser/src/lexer/token.rs	21.97% <25.00%> (-0.75%)	⬇️
analyzer/src/namespace/types.rs	84.83% <100.00%> (-0.23%)	⬇️
analyzer/src/traversal/expressions.rs	92.82% <100.00%> (+0.11%)	⬆️
common/src/numeric.rs	100.00% <100.00%> (ø)
parser/src/grammar/expressions.rs	88.33% <100.00%> (ø)

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[sbillig]

Looks great!