refactor symbol and executor

tests/test_terminal.py

@@ -0,0 +1,22 @@
+from . import *
+from aiomql import Terminal
+
+
+class TestTerminal(BaseTest):
+    terminal = Terminal()
+    async def test_version(self):
+        res = await self.terminal.version
+        assert len(res) == 3
+
+    async def test_info(self):
+        res = await self.terminal.info()
+        assert res.connected is True
+
+    async def test_error(self):
+        res = await self.terminal.last_error()
+        assert res.code == 1
+
+    async def test_symbols_get(self):
+        res = await self.terminal.symbols_get()
+        sym = next(res)
+        assert isinstance(sym.name, str)