Thymeleaf HTML5 compliance and consistency

[shinedeveloper]

1. Consider data-th-attributes instead of th:attributes

2. Consider renaming iter to status or stat

3. Make sure you use stat.index instead of stat.count-1 and stat.count instead of stat.index+1

4. Decide whether minimize or maximize size of SpEL ${} when Thymeleaf evaluation can work as well. That is particularly important for single text values like th:text="'sample'" or th:text="${'sample'}" and stick with the strategy

5. Make sure URLs are all absolute using @{/sample}.

6. Decide whether you should use ModelAndView as a return type or Model or ModelMap as an input parameter while returning just String viewName. The other strategy is more validation friendly and probably more common in the wild.

7. Decide whether you want to use .html in the URLs or not and stick with it consistently.