Update version number to 1.3.20

Author: lucdion

CHANGELOG.md

@@ -7,7 +7,7 @@
 
 # Change Log
 
-## [1.3.19](https://github.com/layoutBox/FlexLayout/releases/tag/1.3.19)
+## [1.3.20](https://github.com/layoutBox/FlexLayout/releases/tag/1.3.20)
 Released on 2020-05-29
 
 Add baseline item support. 

FlexLayout.podspec

@@ -1,7 +1,7 @@
 
 Pod::Spec.new do |spec|
   spec.name         = "FlexLayout"
-  spec.version      = "1.3.19"
+  spec.version      = "1.3.20"
   spec.summary      = "FlexLayout"
   spec.homepage     = "https://github.com/lucdion/FlexLayout.git"
   spec.license      = "MIT license"