confgen(IgnoreRows): add a specifier to ignore some rows of data

[Kybxd]

For example, we can add a new specifier #IGNORE to prevent ID=2 row from exporting, so it' will not be generated to JSON/Text/Bin file.
The #IGNORE column cell should be parsed by strconv.ParseBool, which can accept 1, t, T, TRUE, true, True, 0, f, F, FALSE, false, False.

ID	Name	Desc	#IGNORE
map<uint32, Item>	string	string
Item’s ID	Item’s name	Item’s desc
1	Apple	A kind of delicious fruit.
2	Orange	A kind of sour fruit.	true
3	Banana	A kind of calorie-rich fruit.

{
    "itemMap": {
        "1": {
            "id": 1,
            "name": "Apple",
            "desc": "A kind of delicious fruit."
        },
        "3": {
            "id": 3,
            "name": "Banana",
            "desc": "A kind of calorie-rich fruit."
        }
    }
}

[wenchy]

The specifier need to be discussed in depth. In order to be simple, easy to understand, extensible, and obey consistent design.

The general form can be defined as #VERB(params).

So nominated forms are:

• #IGNORE
• #IGNORE(row)