Add missing write method

src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB6.kt

@@ -409,6 +409,10 @@ class BTreeDB6 private constructor(val file: File, private var reader: RandomAcc
 		}
 	}
 
+	fun write(key: ByteKey, value: ByteArray) {
+		write(key, value, 0, value.size)
+	}
+
 	private fun allocBlock(type: BlockType): Block {
 		return allocBlocks(type, 1)[0]
 	}