set text color has no effect

[IlyaEremin]

For example:

bt.addPiece(new BabushkaText.Piece.Builder("please\n")
            .style(Typeface.BOLD)
            .textSize(35)
            .build());
bt.addPiece(new BabushkaText.Piece.Builder("change textcolor")
            .textSize(20)
            .build());
bt.display();

I get textview with black text colour (default color)
Then I call

bt.setTextColor(getResources().getColor(R.color.white));

And textColor remains black.
I understand what there is no built-in ability to change spannable text colour on the fly, but it's would be very helpful function.

[hboregio]

Merged.