support Operator Precedence (e.g. `A and B or X and Y`)

[nitram509]

Currently the parser is not able to build a valid AST for expressions with combined operators like e.g. A and B or X and Y.

• Hint: See DMN spec for "Operator precedence"
• Hint: See (skipped) test: Test_eval_multiple_operators_with_logical_precedence() for a starting point