development: Preparation for 2.3.21 release

Material.podspec

 Pod::Spec.new do |s|
   s.name = 'Material'
-  s.version = '2.3.20'
+  s.version = '2.3.21'
   s.license = 'BSD-3-Clause'
   s.summary = 'Material is an animation and graphics framework that is used to create beautiful applications.'
   s.homepage = 'http://materialswift.com'

README.md

@@ -39,7 +39,7 @@ We moved all sample projects to a separate repo named [Samples](https://github.c
 - [x] Sample Projects
 - [x] And More...
 
-## Releasing November 2016
+## Releasing December 2016
 
 - [x] Reminders
 - [x] Text Editor

Sources/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>2.3.20</string>
+	<string>2.3.21</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>