TrueSkill - Through Time

Rust port of TrueSkillThroughTime.py.

Other implementations

• ttt-scala
• ChessAnalysis #F
• TrueSkillThroughTime.jl
• TrueSkillThroughTime.R

Todo

• Implement approx for Gaussian
• Add more tests from TrueSkillThroughTime.jl
• Time needs to be an enum so we can have multiple states (see batch::compute_elapsed())
• Add examples (use same TrueSkillThroughTime.(py|jl))
• Add Observer (see argmin for inspiration)