feat: ignore camelCase, PascalCase, snake_case, etc.

[jjangga0214]

In markdown snippet, Grammarly complains about name of programming variable, function, class, etc.

Whether to check if variable name is correct should be done by configuring linter, like eslint-plugin-markdown.

1. I think it'd be better to ignore, by default, various cases widely used in programming, like kebab-case, CAPITAL_SNAKE_CASE, camelCase, etc.

2. Or the extension may disassemble those words. For example, parse the word 'changedFiles' and give it to Grammarly by 'changed files'. So if there's a type in the variable, like 'chagedFiles'(n is missing), Grammarly will complain.

3. Providing a config option to disable Grammarly for fenced code snippet(```) is also good, if comments in the snippet are OK to be ignored.