MAPG-43 initial classes for DB handling

src/Database/RawExpression.php

@@ -0,0 +1,16 @@
+<?php namespace MapGuesser\Database;
+
+class RawExpression
+{
+    private string $expression;
+
+    public function __construct(string $expression)
+    {
+        $this->expression = $expression;
+    }
+
+    public function __toString(): string
+    {
+        return $this->expression;
+    }
+}