trying logarithmic scaling for opacity
Merge pull request #143 from jvoigtlaender/log-opacity

trying logarithmic scaling for opacity
fixes #142
new images for legend, refs #143
Render movement arrows on top of markers, with thicker lines. refs #105
AI: Switch to phase 2 mode during countdown. (fixes #127)
Correct number of turns
Merge branch 'master' of https://github.com/zrho/afp