8867 fill transparency

[ES-Solar]

*modified PSL_setcolor method to preserve transparency of pen or fill colors if when the other is set.

The problem was the fill transparency was being changed when the to be the pen transparency if the fill transparency wasn't explicitly specified.

Fixes #8867

Reminders

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[joa-quim]

Thanks, that situation is now fixed and tests do not show any obviously related failures.

[joa-quim]

Sorry, found this too late. There is no fillTransparency.ps and the fillTransparency.ps.dvc wrongly ended up in baseline\postscriptlight (which should have fillTransparency.ps) instead of test\baseline. The DVC is horrible, I know.