Localize the documentation

[oleg-nenashev]

Summary

I suggest localizing the docs a bit so that there are both Japanese and English versions. We could do it as following:

• Split README and README_ja.md in root files, add cross-references
• Add docs/ja directory where the localized versions of the docs would reside
• Arrange the content accordingly

Later we could add more localizations and add support for it on WireMock.org if there is demand from end users

References

No response