Update podspec

Author: Bryan Clark

SwiftTweaks.podspec

@@ -1,12 +1,12 @@
 Pod::Spec.new do |s|
   s.name         = "SwiftTweaks"
-  s.version      = "1.1"
+  s.version      = "3.0"
 
   s.summary      = "Tweak your Swift-based app on-device."
   s.description  = "SwiftTweaks is a way to adjust your Swift-based iOS app on-device without needing to recompile. Read more about it on our blog: http://engineering.khanacademy.org/posts/introducing-swifttweaks.htm"
 
   s.homepage     = "https://github.com/Khan/SwiftTweaks"
-  s.screenshots = "https://raw.githubusercontent.com/Khan/SwiftTweaks/master/Images/SwiftTweaks%20Demo.gif", "https://raw.githubusercontent.com/Khan/SwiftTweaks/master/Images/SwiftTweaks%20Overview.png"
+  s.screenshots  = "https://raw.githubusercontent.com/Khan/SwiftTweaks/master/Images/SwiftTweaks%20Overview.png"
 
   s.license      = { :type => "MIT", :file => "LICENSE" }
 
@@ -16,7 +16,7 @@ Pod::Spec.new do |s|
   # s.platform     = :ios, "8.0"
   s.ios.deployment_target = 8.0
 
-  s.source       = { :git => "https://github.com/Khan/SwiftTweaks.git", :tag => "v1.0", :submodules => true }
+  s.source       = { :git => "https://github.com/Khan/SwiftTweaks.git", :tag => "v3.0", :submodules => true }
   s.source_files = "SwiftTweaks/**/*.swift"
   s.resources = "SwiftTweaks/*.xcassets"