Added NoUserInfo, NoMessageText and HandlerUsed error types to decrease the amount of unwraps

src/errors.rs

@@ -0,0 +1,11 @@
+#[derive(thiserror::Error, Debug)]
+#[error("No user info found")]
+pub struct NoUserInfo;
+
+#[derive(thiserror::Error, Debug)]
+#[error("Message text not found")]
+pub struct NoMessageText;
+
+#[derive(thiserror::Error, Debug)]
+#[error("Handler was already used")]
+pub struct HandlerUsed;