Fixed compiler warning in MicroViewSlider.
In drawFace, majorLine could be left uninitialised if style was invalid
(although this couldn't happen with the current code).
Also cleaned up the WIDGETSTYLE tests.
Changed vertical slider direction.
Low values at the bottom. High values at the top.
Merge pull request #9 from MLXXXp/vSlider_reverse_2

Reverse direction of virtical sliders