Bump version to 0.4.9
Don't display the save command in the main menu
Update vs engine changes
Add two more screensaver tests
Make OverloadedStrings a default extension
Use the debug option to exit the game session after a given time
Test animations in testDefense
Define multi-floor lifts, similar to starcases
Replace Descend k by Ascend (-k)
Let levels go up, not down

There's artificial gravity on this toroid spaceship and the player
starts in the outermost level.
Lower human IQ until pathfinding is implemented
Define travisTests
Tune parameters of frontend frame flushes in noMore mode
Add peek game mode and tweak tests
Limit the AI use of difficult abilities
Let scrolls ascend, not descend, unlike in LambdaHack
Make peek game mode more similar to campaign mode
Add wall caches that create items
Update scores
Update Makefile according to engine changes