Release of new version 6.4.5

Signed-off-by: Jack Cherng <jfcherng@gmail.com>

Author: jfcherng

CHANGELOG/CHANGELOG_v6.md

@@ -2,6 +2,19 @@
 ## VERSION 6  UNIFIED
 
  * Version **6.4** - Add renderer option: lineNumbers
+   * 2020-02-24 14:47  **6.4.5**  CSS tweaks
+      * 36799b9 SideBySide shows a stripe for nonexistent lines
+      * 6b7e36b Update readme
+      * 8b89bbc Add a const for indicating showing all contexts
+      * bd2c868 Make empty cells have height via CSS
+      * 3ae6da1 Make coding thoughts more clear
+      * 0394a74 Tidy Codes
+      * 7093932 Update SideBySide screenshot
+      * abb8955 Improve SideBySide CSS for nonexistent blocks
+      * 8cb05e8 Add keywords to composer.json
+      * f061297 Update example/README.md
+      * f861a3f Add more cases to example text sources
+      * 34786fa Update example/README.md
    * 2020-02-13 14:16  **6.4.4**  Fix SideBySide wrong new line number
       * 7397cbe Tidy codes
       * 215209d Fix SideBySide wrong new line number
@@ -129,4 +142,4 @@
       * 177146e Rename Diff to Differ
       * 0a30b27 Renderer::render() rather than Diff::render()
       * deb9ed3 Revise phpdoc
-      * d8606b7 Release of new version 5.1.0
+      * d8606b7 Release of new version 5.1.0