[TabWidget] configure title alignment & strange naming

[smir-ant]

Feature Description

TabWidget has only 1 property(current-index) and 1 config option (title). This is a huge limitation.
But i'm here cuz title is left-align by default , but i think that add
in property <TextHorizontalAlignment> title-alignment: left;
and it will be more customizable:

text := Text {
    vertical-alignment: center;
    horizontal-alignment: root.title-alignment;  // instead of horizontal-alignment: left;
}

it will be work with doc example

TabWidget {
        Tab {
            title: "First";
            Rectangle { background: orange; }
        }

but now we can have

TabWidget {
        Tab {
            title: "First";
            title-alignment: center;
            Rectangle { background: orange; }
        }

p.s. I think it would be nice to add the font size config too!!!

and why is it named as TabWidget? why not Tabs?

we don't have ButtonWidget - its a Button, we don't have LineEditWidget - only LineEdit, but TabWidget...