* single tap picker (improvements, policies and promotions), tbd: split button
* improvement and promotion pickers: using split buttons featuring a question mark. allows single-tap choice.
* improvement picker and promotion picker: show "pick now" to the right of the button
* implemented single tap move
- units stay selected after move (to go on moving)
- and they are de-selectable by taping them again (to abort moving)
* unit movement: mark the reachable spots clearly to avoid accidental movement
* unit action: when an exclusive decision is made, deselect unit
* clicking on the unit information in the UnitTable will show that unit + minor fixes
* siege units won't show movement hints when set up, while packing up does not cost any movement points
* workers: highlight button when constructing an improvement, won't sleep then
* fixed units not being de-selected when clicking the UnitTable or "next unit" button
* zooming forwards clicks on to the map, so we need to deselect units in that case
* clean up branch
* added "Move units with a single tap" to options menu
* Notifications scroll: keep scrolling position on game update if it's still the same list
* tech picker shows current/recent technology centered on the screen
* using NotificationAction interface to attach various actions to Notifications
* tech notifications: center on tech that was discovered
* improved CityButton
* keep city button out of the way if a unit on the city tile is selected
* fixed city button to be clickable always. however this hides units behind it
* added click area for city buttons in an own layer, so the units render in front and the city button click area handles the clicks
* city button: simplified code
* unit action: when an exclusive decision is made, deselect unit
* clicking on the unit information in the UnitTable will show that unit + minor fixes
* siege units won't show movement hints when set up, while packing up does not cost any movement points
* workers: highlight button when constructing an improvement, won't sleep then
* fixed broken saved game
* show messages if exploring is done or WorkerAutomation is done
* Revert "siege units won't show movement hints when set up, while packing up does not cost any movement points"
This reverts commit b805993a
