liq| er| uv|: +_exportUVFromNodePlug(), _OLD_WAY_ for new mesh data structure.(NOTE: maya mesh must be trianglated.)
liq| er| uv|: use new way to export mesh data. - 1.
liq| er| uv|: use new way to export mesh data. - 2. refactoring
liq| er| uv|: use new way to export mesh data. - 3. remove unused code