Remove obsolete file

db/src/error.rs

@@ -1,22 +0,0 @@
-#[derive(Debug, PartialEq)]
-pub enum Error {
-	/// Low level database error
-	DatabaseError(String),
-	/// Invalid block
-	CannotCanonize,
-	/// Uknown parent
-	UnknownParent,
-	/// Ancient fork
-	AncientFork,
-}
-
-impl From<Error> for String {
-	fn from(e: Error) -> String {
-		match e {
-			Error::DatabaseError(s) => format!("Database error: {}", s),
-			Error::CannotCanonize => "Cannot canonize block".into(),
-			Error::UnknownParent => "Block parent is unknown".into(),
-			Error::AncientFork => "Fork is too long to proceed".into(),
-		}
-	}
-}