Setting textangle, valign and halign does not work

This is a quick and dirty fix so that one can set PlotLabel (and DataLabel) angle, valign and halign by e.g. 
```julia
add(p, PlotLabel(.5, .5, "Histogram", color="red",fontsize=5.0,angle=20.0,halign="right"))
```

There is however a cosmetic problem here because now the default values (angle=0. and valign & halign="center") are set in two locations separately; In the Winston.jl/make() and in the paint.jl/TextObject(). Merge this if you want a quick temporary fix for this.