Fix review points

Fix review points

- Fix headers hierarchy
- Improve accessibility:
 	- set mouse pointer
	- make rows focusable
	- open on key press
	- add tooltip with "title"
	- add role and aria attributes
- Rename `ParsedLog` to `ParsedLogLine`
- Add docs to `ReversedFileReader`'s implementation of `Iterator`'s methods
- Add docs to `ParsedLogIterator`'s implementation of `Iterator`'s methods
- Remove unnecessary comment
- Add more test for parsing log lines and fix some edge cases
- Fix function name in snake-case to camelCase
- Remove `DIRECTORY_SEPARATOR`