feat(refactor): Removes bignumber.js as utils dependency, remove obsolete utils, enhance unit utils

[rossbulat]

Changelog

Breaking changes: Bumps @w3ux/utils major version.

• Removes bignumber.js as a w3ux dependency, and improves types support for the functions that were using BigNumber.
• planckToUnit and unitToPlanck now allow BigInt | string | number as their input value.
• planckToUnit returns a string, whereas unitToPlanck returns a BigInt. The prior returns string instead of number as there is no guarantee the resulting value will be a within the max supported value.
• More test scenarios for the above functions.
• minDecimalPlaces allow BigInt | string | number as its input value, and retains commas if present in input.
• Covered more test scenarios for minDecimalPlaces.

The following utils have been removed as a result of BigNumber.js being deprecated:

• greaterThanZero - syntax sugar over BigNumber.js syntax.
• isNotZero - syntax sugar over BigNumber.js syntax.
• evalUnits - unused in Polkadot Cloud apps.
• stringToBigNumber - no longer required.
• transformToBaseUnit - duplicate of planckToUnit.

Docs:

• Update https://github.com/w3ux/docs with updated signatures, added functionality, and examples.