Parse the used data information of the import template. If the data attribute
name is not changed, it'll ignore.

e.g.,
input: a:b, c, ...obj
output: {a: b}

@inner
@param {string} value the data value
@return {?Object}
function parseTplDataInfo(value) {
    value = value.substring(1, value.length - 1);
    let items = value.split(',');
    let dataObjAttrs = {};
    items.forEach(item => {
        let colonIdx = item.indexOf(':');
        if (colonIdx !== -1) {
            let key = item.substring(0, colonIdx).trim();
            let value = item.substr(colonIdx + 1).trim();

            key === value || (dataObjAttrs[key] = value);
        }
    });

    return Object.keys(dataObjAttrs).length ? dataObjAttrs : null;
}