Add TrendRider Strategy to Cryptocurrencies section

[darkvolg]

Hi! Would like to add TrendRider Strategy to the Backtesting and Live Trading → Cryptocurrencies section.

What it is

An open-source Freqtrade strategy that implements a cascading early-loss-cut exit logic (2h@-1.5% → 4h@0% → 8h@+0.5% → 16h@+1% → 24h force). Written in Python, MIT licensed.

Why it fits here

• It's a systematic-trading strategy, not just a library — full Freqtrade config, hyperopt setup, and backtest data included.
• Live bot is publicly trading with stats updated every 5 minutes at trendrider.net/live (~70 trades, ~65% WR as of this PR).
• Includes written post-mortem of how the cascading exit was developed (13 days of breakeven → profitable after the fix).

Placed at the end of the Cryptocurrencies table, alongside Hummingbot / cryptotrader-core.

Happy to adjust wording or re-categorize if you'd prefer a different placement. Thanks!