Apply suggestions from code review

Co-authored-by: Clément Renault <[email protected]>

heed/src/txn.rs

@@ -7,11 +7,11 @@ use crate::{Env, Result};
 
 /// A read-only transaction.
 ///
-/// ## LMDB Limitation
+/// ## LMDB Limitations
 ///
-/// It's a must to keep read transaction short lived.
+/// It's a must to keep read transactions short-lived.
 ///
-/// Active Read transactions prevent reuse of pages freed
+/// Active Read transactions prevent the reuse of pages freed
 /// by newer write transactions, thus the database can grow quickly.
 pub struct RoTxn<'e> {
     pub(crate) txn: *mut ffi::MDB_txn,
@@ -58,8 +58,10 @@ fn abort_txn(txn: *mut ffi::MDB_txn) {
 
 /// A read-write transaction.
 ///
-/// Only one [RwTxn] may exist on the same environnement at the same time,
-/// it two exist the new one may wait on a Mutex for [RwTxn::commit] or [RwTxn::abort] of
+/// ## LMDB Limitations
+///
+/// Only one [RwTxn] may exist in the same environment at the same time,
+/// it two exist, the new one may wait on a Mutex for [RwTxn::commit] or [RwTxn::abort] of
 /// the first one.
 pub struct RwTxn<'p> {
     pub(crate) txn: RoTxn<'p>,