Fix wrong pair-content in strategy-analysis notebook and documentation

closes #4399

freqtrade/templates/strategy_analysis_example.ipynb

@@ -40,7 +40,7 @@
     "# Location of the data\n",
     "data_location = Path(config['user_data_dir'], 'data', 'binance')\n",
     "# Pair to analyze - Only use one pair here\n",
-    "pair = \"BTC_USDT\""
+    "pair = \"BTC/USDT\""
    ]
   },
   {
@@ -54,7 +54,9 @@
     "\n",
     "candles = load_pair_history(datadir=data_location,\n",
     "                            timeframe=config[\"timeframe\"],\n",
-    "                            pair=pair)\n",
+    "                            pair=pair,\n",
+    "                            data_format = \"hdf5\",\n",
+    "                            )\n",
     "\n",
     "# Confirm success\n",
     "print(\"Loaded \" + str(len(candles)) + f\" rows of data for {pair} from {data_location}\")\n",