New Sendex Formula

[MajinPierce]

• need a new sendex formula that more accurately describes climbing conditions
  • should take into consideration precipitation
    • current precipitation
    • precipitation from last few days
  • ideally should map to a 0-100 scale, 0 worst 100 best
• potentially have area specific sendex offsets/multipliers
  • for example TWall might be positively skewed to a slightly lower temperature than other areas