Simplifying adding extra character encodings

[balbusm]

Hi, Only the most common subset of character encodings is supported. It's pretty cumbersome to add new encoding in case of missing one. This PR utilizes ServiceLoader in order to simplify adding extra/custom character encodings.

I also added Japanese encoding (CP932).

[sonarqubecloud[bot]]

Quality Gate failed

Failed conditions
B Reliability Rating on New Code (required ≥ A)

See analysis details on SonarQube Cloud

Catch issues before they fail your Quality Gate with our IDE extension SonarQube for IDE