update Clear flag documentation

closes #2

Author: sentriz

README.md

@@ -54,7 +54,7 @@ The behaviour of writing can be configured with some bitset flags
 
 The options are
 
-- `Clear` which clears existing metadata before writing the new
+- `Clear` which indicates that all existing tags not present in the new map should be removed
 - `DiffBeforeWrite` which won't modify the file on disk if the new metadata is the same as the old
 
 The options can be combined the with the bitwise `OR` operator (`|`)

taglib.go

@@ -225,7 +225,7 @@ func ReadProperties(path string) (Properties, error) {
 type WriteOption uint8
 
 const (
-	// Clear indicates that all existing tags not present in the map should be removed.
+	// Clear indicates that all existing tags not present in the new map should be removed.
 	Clear WriteOption = 1 << iota
 
 	// DiffBeforeWrite enables comparison before writing to disk.