Replace 'BTC_XXX' with 'XXX/BTC' for pairs and 'XXX_BTC' for files

freqtrade/tests/testdata/pairs.json

@@ -1,26 +1,26 @@
 [
-    "BTC_ADA",
-    "BTC_BAT",
-    "BTC_DASH",
-    "BTC_ETC",
-    "BTC_ETH",
-    "BTC_GBYTE",
-    "BTC_LSK",
-    "BTC_LTC",
-    "BTC_NEO",
-    "BTC_NXT",
-    "BTC_POWR",
-    "BTC_STORJ",
-    "BTC_QTUM",
-    "BTC_WAVES",
-    "BTC_VTC",
-    "BTC_XLM",
-    "BTC_XMR",
-    "BTC_XVG",
-    "BTC_XRP",
-    "BTC_ZEC",
-    "USDT_BTC",
-    "USDT_LTC",
-    "USDT_ETH"
+    "ADA/BTC",
+    "BAT/BTC",
+    "DASH/BTC",
+    "ETC/BTC",
+    "ETH/BTC",
+    "GBYTE/BTC",
+    "LSK/BTC",
+    "LTC/BTC",
+    "NEO/BTC",
+    "NXT/BTC",
+    "POWR/BTC",
+    "STORJ/BTC",
+    "QTUM/BTC",
+    "WAVES/BTC",
+    "VTC/BTC",
+    "XLM/BTC",
+    "XMR/BTC",
+    "XVG/BTC",
+    "XRP/BTC",
+    "ZEC/BTC",
+    "BTC/USDT",
+    "LTC/USDT",
+    "ETH/USDT"
 ]