Test coverage for implicit grant.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>
Added missing tearDown method.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>
Refactoring.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>
Refactoring client credentials grant and adding test coverage.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>
Refresh token grant test coverage.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>