Add real time validation for other languages

[davsclaus]

With the jsonpath laid the foundation for other languages, we can take a look at maybe adding support for other languages that are popular to use.

We could refactor the settings UI to have a panel where you can turn on|off the languages we support.

• simple
• jsonpath
• xpath
• spel
• groovy
• mvel
• ognl etc

[davsclaus]

Okay so the UI has been altered so there is a validation page in the preference where we have room for adding more languages