reorganize the library into three folders lib, contrib and core

Write unittests with pytest
Make all functions and method signatures as keyword only arguments

tests/unittests/test_ticks.py

@@ -0,0 +1,26 @@
+from datetime import datetime
+
+from aiomql.lib.ticks import Ticks, Tick
+from pandas import Series
+
+class TestTicks:
+    async def test_tick(self, mt):
+        btc_tick = await mt.symbol_info_tick("BTCUSD")
+        btc_tick = Tick(**btc_tick._asdict())
+        tick_dict = btc_tick.dict(include={'ask', 'bid', 'time', 'volume'})
+        assert isinstance(btc_tick, Tick)
+        assert isinstance(tick_dict, dict)
+        assert 'ask' in tick_dict
+        assert 'bid' in tick_dict
+        assert 'volume_real' not in tick_dict
+
+    async def test_ticks(self, mt):
+        start = datetime(year=2023, month=10, day=5)
+        ticks = await mt.copy_ticks_from("BTCUSD", start, 10, mt.COPY_TICKS_ALL)
+        ticks = Ticks(data=ticks)
+        assert isinstance(ticks, Ticks)
+        assert len(ticks) == 10
+        assert isinstance(ticks[0], Tick)
+        bids = ticks['bid']
+        assert len(bids) == 10
+        assert isinstance(bids, Series)