add map accessor to Database; move cork interface

Signed-off-by: Jason Volk <jason@zemos.net>

src/database/cork.rs

@@ -1,6 +1,6 @@
 use std::sync::Arc;
 
-use crate::Engine;
+use crate::{Database, Engine};
 
 pub struct Cork {
 	db: Arc<Engine>,
@@ -8,6 +8,20 @@ pub struct Cork {
 	sync: bool,
 }
 
+impl Database {
+	#[inline]
+	#[must_use]
+	pub fn cork(&self) -> Cork { Cork::new(&self.db, false, false) }
+
+	#[inline]
+	#[must_use]
+	pub fn cork_and_flush(&self) -> Cork { Cork::new(&self.db, true, false) }
+
+	#[inline]
+	#[must_use]
+	pub fn cork_and_sync(&self) -> Cork { Cork::new(&self.db, true, true) }
+}
+
 impl Cork {
 	#[inline]
 	pub(super) fn new(db: &Arc<Engine>, flush: bool, sync: bool) -> Self {