Add expiresAt and isExpired params to SecurityToken (issue1133044)

[lindner]

Reviewers: shindig.remailer_gmail.com,


Please review this at http://codereview.appspot.com/1133044/show

Affected files:
  M UPGRADING
  M  
java/common/src/main/java/org/apache/shindig/auth/AnonymousSecurityToken.java
  M  
java/common/src/main/java/org/apache/shindig/auth/BasicSecurityToken.java
  M  
java/common/src/main/java/org/apache/shindig/auth/BasicSecurityTokenDecoder.java
  M  
java/common/src/main/java/org/apache/shindig/auth/BlobCrypterSecurityToken.java
  M  
java/common/src/main/java/org/apache/shindig/auth/BlobCrypterSecurityTokenDecoder.java
  M  
java/common/src/main/java/org/apache/shindig/auth/ForwardingSecurityToken.java
  M java/common/src/main/java/org/apache/shindig/auth/SecurityToken.java
  M  
java/common/src/test/java/org/apache/shindig/common/testing/FakeGadgetToken.java
  M  
java/gadgets/src/test/java/org/apache/shindig/gadgets/http/AbstractHttpCacheTest.java
  M  
java/gadgets/src/test/java/org/apache/shindig/gadgets/oauth/GadgetOAuthCallbackGeneratorTest.java
  M  
java/gadgets/src/test/java/org/apache/shindig/gadgets/oauth/OAuthRequestTest.java
  M  
java/server/src/test/java/org/apache/shindig/server/endtoend/EndToEndTest.java
  M  
java/social-api/src/main/java/org/apache/shindig/social/core/oauth/OAuthAuthenticationHandler.java
  M  
java/social-api/src/main/java/org/apache/shindig/social/core/oauth/OAuthSecurityToken.java
  M  
java/social-api/src/main/java/org/apache/shindig/social/sample/oauth/SampleOAuthDataStore.java