XML introduced

This version is simpler to use and introduces some new annotations

• New @XML annotation
• New @XPath annotation
• Removed multiples selectors per field, only one allowed
• No more selectors for inner classes. Selectors now are exclusive to fields, making it less confusing
• No more selector format types, use @Selector for css selector and @XPath for xpath
• Downgrade to java 11, this way webgrude can be used on older JVM again