Backtester: custom interval support (#1115)

* add backtester support

* Prevent live data custom candles, prevent nanosecond candles

* test coverage

* a more interesting rsi strategy result

* actual custom candle and proper strat date

* add test to old funk

* typos 🌞 🌞

* this was definitely worth failing linting for

* Adds stricter processing and adapts to it

* now compat with partial and absent candles

* test fixes, zb fixes

* fix more introduced bugeroos

* fix more introduced bugeroosx2

* linting for one space is so annoying

* addresseroos niteroos

* Update backtester/engine/setup.go

Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

testdata/http_mock/zb/zb.json

@@ -2135,6 +2135,25 @@
      "queryString": "market=btc_usdt\u0026since=1598918400000\u0026size=1000\u0026type=1day",
      "bodyParams": "",
      "headers": {}
+    },
+    {
+     "data": {
+      "data": [
+       [
+        1674489600000,
+        22202.37,
+        22222,
+        22000.03,
+        22033.84,
+        2321.1898
+       ]
+      ],
+      "moneyType": "USDT",
+      "symbol": "BTC"
+     },
+     "queryString": "market=btc_usdt\u0026since=1674432000000\u0026size=1000\u0026type=1day",
+     "bodyParams": "",
+     "headers": {}
     }
    ]
   },