game: don't start new game on rotate while intro is playing

when rotating while intro is playing, we have no retained config,
because game hasn't been resumed yet. just skip intro instead to
load game from persisted state.
currentStone/Wheel: don't block currentStone at board border

allows for dragging to begin right within the wheel.
game: vibrate on every move
new preference: vibrate on stone move / vibrate on stone set. vibrate on stone snap.
currentStone: snap to correct position after moving. don't leave stone inbetween fields
layout update for game menu dialog
join dialog: layout updates
game: added sound effect for falling stone
game: vibrate on stone set on first impact of StoneRollEffect
game: don't vibrate when start dragging stone

only vibrate on long press, which starts dragging. when user moves
the stone by intention, no vibrate is neccessary
styles: add api dependend styles for dialogs
about: added landscape layout, added special thanks, added market url
game menu: nicer custom game button
custom game: add support for Blokus Duo (2 players 2 colors, 2 players 4 colors)
custom game: set size of field
view: always redraw on effect finish
preferences: put sounds to the top of list
undo effect: fix wrong position on fields != 20
finish activity: small layout changes
remove unused startscreen optionsmenu