Update project description and travis-ci.org status image.
Add tests for all classes exist check.
Implement getGrantType() and corresponding test cases.
Implement getTokenType() and corresponding test cases.
 Update with initial doxygen, no debug yet.
Use README.txt as @mainpage.
Update config.doxy with CASE_SENSE_NAMES = YES.
Add post-commit hook so update _gh_pages automatically.
Enable HTML_TIMESTAMP so auto doxygen update will show build time.
Implement getResponseType() and corresponding test cases.
Implement skeleton for validateRequest() with corresponding test case.
Document exceptions error message, copy from rfc6749.
Revamp both exceptions and test cases.
Implement most test cases for validateRequest().
Implement validateRequest() and test case for AccessTokenRequest.
Revamp parameter filtering as Oauth2::getParam() so can reuse else where.
Fix typo in getParam().
Add ResponseType skeleton and test cases.
Update README.md with reference links.
Reformat README.md with pandoc.