Changelog for intricacy-0.4.1

This is an abbreviated summary; see the git log for gory details. 0.4.1: Concurrency on server; no more freezes while it checks a solution. Misc minor UI fixes. 0.4: Sound effects (thanks linley). Animate to show the two physics phases (thanks dormir). Help screens. Help text for buttons and metagame. Deneutralised metagame terminology. Tutorial tweaked. Various UI improvements (thanks Quicksand-S and dormir) 0.3: Mouse control. Improvements to curses UI - handle resizing; show keys; allow rebinding. Shortened tutorial drastically. Other levels now in 'tutorial-extra/'. Improve handling inaccessible servers. Added background. First version uploaded to hackage. Scoring tweak: empty slots are accessed iff all non-empty slots are. Detailed game info in README. Hover text for UI buttons. Marks. Lock testing in edit mode. Significant bugs fixed: editor, lockfile reader, and validity checker were not in accordance on what is allowed as the root of a spring. SDL UI was redrawing the screen on every mouse movement. curses UI wasn't refreshing properly on async flag. stale notes weren't getting refreshed. retired display got stuck on changing codename. you couldn't move into the bolthole with keyboard commands. 0.2: First public release