Settings: Allow smaller SlimPIE sizes + multiDpi fixes (2/2)

Due team, user and kanger wishes I needed to do again something :p
Hopefully now really the last thing :D Is now in full range as well usable
for higher dpi then our stock dpi

This commit does:
- allow bigger size range for SlimPIE layout
- icon are now resized on smaller sizes (only then) then default size
  which allows much smaller overall size
- slight better positiong of the icons in the button item
- Fix: reported issues custom Icons are sometimes to small
- Fix: reported issue that estimated container size took not PIE_SIZE
  into account (follows now on every dpi and size the activation point)
- Fix: Settings style seekbar resets sometimes to last setted value
- Settings: a bit code rearrangement (not needed but I was bored :p)

And now really finished :p

cheers

Change-Id: I6917830262f1c1bf31f0175368daa7d9e187ad9c