InvalidPathException in RelationalOperator depending on Locale

[renekrie]

RelationalOperator.fromString(operatorString) will throw an InvalidPathException if the default Locale is tr_TR and operatorString is "in".

This happens because the implementation applies an .toUpperCase on the operatorString without passing a Locale. At least in Turkish, and maybe in other orthographies as well, the uppercase variant does not match what was defined as the uppercase operatorString in RelationalOperator.

I'm going to supply a fix for this.