Add support not operator in expression evaluation

[darenkeck-dev]

Currently when extracting an expression from modelica-json, the logical not (a !) is not extracted.

                {
                  "not": true, // <-- not extracted 
                  "arithmetic_expressions": [
                    {
                      "name": "have_SZVAV"
                    }
                  ]
                }

Update the parser to extract and include the logical not in the intermediate format.

Update the interpreter's expression evaluation so it handles the not operator.