added database_pool crate, for pool handling and migrations

crates/database_pool/src/migrations.rs

@@ -0,0 +1,15 @@
+use sqlx::migrate::MigrateError;
+use sqlx::{Pool, Sqlite};
+
+pub async fn run_migrations(pool: &Pool<Sqlite>) -> Result<(), MigrateError> {
+    match sqlx::migrate!("../database").run(pool).await {
+        Ok(ok) => {
+            println!("Migrations are OK");
+            Ok(ok)
+        }
+        Err(e) => {
+            eprintln!("Failed to run migrations!");
+            Err(e)
+        }
+    }
+}