CAS-1306: Ensure OAuth parameters are consistent in logs. 

Basically, want to ensure that the OAuth parameter names that are logged alongside their values are actually those that are defined and declared by the OAuth module. 

Also, the following has happened:

1. Will not log the `clientSecret`. 
2. Fixed instances of trailing `else` clauses
3. Fixed instance of lines extending the CS limit
4. Ensure properly closure of JSON resources through `IOUtils.closeQuietly`
5. Fixed an instance where the `clientSecret` was actually logged again instead of the `code`