Add slackware package database parser

cli/main.cpp

@@ -0,0 +1,14 @@
+#include <filesystem>
+#include <iostream>
+#include "katja/database.hpp"
+
+int main()
+{
+    for (const auto& entry : std::filesystem::directory_iterator(katja::database))
+    {
+        katja::database_package database_entry{ entry.path().filename() };
+
+        std::cout << database_entry.to_string() << std::endl;
+    }
+    return 0;
+}