feat(ios): backgroundColor for RefreshControl

[m1ga]

Adds the ability to change the backgroundColor of the refresh box:

Test

const win = Ti.UI.createWindow();
let counter = 0;
function genData() {
    const data = [];
    for (let i = 1; i <= 3; i++) {
        data.push({ properties:{ title: `ROW ${counter + i}` } });
    }
    counter += 3;
    return data;
}
const section = Ti.UI.createListSection();
section.items = genData();
const control = Ti.UI.createRefreshControl({
    tintColor: 'red',
    backgroundColor: "green"
});
const listView = Ti.UI.createListView({
    sections: [section],
    refreshControl: control
});
control.addEventListener('refreshstart', () => {
    Ti.API.info('refreshstart');
    setTimeout(() => {
        Ti.API.debug('Timeout');
        section.appendItems(genData());
        control.endRefreshing();
    }, 2000);
});
win.add(listView);
win.open();

[zo0m]

Thank you

[hansemannn]

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