Incorrect range with quoted string values

[seanyeh]

The range information for quoted string values somehow ignores the quotes when calculating range

might be related to #237

Example

values:
  x: a
  y: "a"

Exprs:

{
    "exprs": {
        "x": {
            "range": {
                "environment": "\u003cproject\u003e/\u003cyaml\u003e",
                "begin": {
                    "line": 2,
                    "column": 6,
                    "byte": 13
                },
                "end": {
                    "line": 2,
                    "column": 7,
                    "byte": 14
                }
            },
            "schema": {
                "type": "string",
                "const": "a"
            },
            "literal": "a"
        },
        "y": {
            "range": {
                "environment": "\u003cproject\u003e/\u003cyaml\u003e",
                "begin": {
                    "line": 3,
                    "column": 6,
                    "byte": 20
                },
                "end": {
                    "line": 3,
                    "column": 7,
                    "byte": 21
                }
            },
            "schema": {
                "type": "string",
                "const": "a"
            },
            "literal": "a"
        }
    },

See that for both x and y, the range end is { line: 3, column: 7 }. But y's range end should be { line: 3, column: 9 }

I also have confirmed that the range also gets off with escaped characters (since the backslash is ignored from the range)