Fixed text positioning

[dive-michiel]

Thanks for the library!

Text positioning parameter was wrong, it used the wrong group code and values.
Fixed using correct group codes + adding secondary alignment points.

Code now works as intended:
Position of text from point: 1 = top-left; 2 = top-center; 3 = top-right; 4 = center-left; 5 = center; 6 = center-right; 7 = bottom-left; 8 = bottom-center; 9 = bottom-right

[dive-michiel]

Example:

    // Added center point for demponstration
    $dxf->setLayer('centerpoint', Color::RED);
    $dxf->addCircle(0, 0, 0, 0.2);

    // Adding 'A' in all the different positions with 0, 0, 0 as center point
    $dxf->setLayer('letters', Color::WHITE);
    $dxf->addText(0, 0, 0, 'A', 8, 1);
    $dxf->addText(0, 0, 0, 'A', 8, 2);
    $dxf->addText(0, 0, 0, 'A', 8, 3);
    $dxf->addText(0, 0, 0, 'A', 8, 4);
    $dxf->addText(0, 0, 0, 'A', 8, 5);
    $dxf->addText(0, 0, 0, 'A', 8, 6);
    $dxf->addText(0, 0, 0, 'A', 8, 7);
    $dxf->addText(0, 0, 0, 'A', 8, 8);
    $dxf->addText(0, 0, 0, 'A', 8, 9);

Output:

[adamasantares]

@u-michiel Hey! Thanks a lot! I've merged.