Add some formatter

[MAKMED1337]

1. Add some formatter/linter for java, that can be used from command line, and can automatically fix some easy problems.
2. And refactor the whole project(except for the GifDecoder I guess) using it, so there will be 0 errors/warning.

[MAKMED1337]

Afterward add https://pre-commit.com/ and add some tutorial how to use it all into the README.md