daff02883034c63c805861c9c8385dc1eb398151 updating the documentation for ramsey_model

================================ DYNARE MAKE CHECK MATLAB RESULTS ================================ | TOTAL: 435 | PASS: 433 | FAIL: 0 | XFAIL: 2 | XPASS: 0

================================ DYNARE MAKE CHECK OCTAVE RESULTS ================================ | TOTAL: 433 | PASS: 431 | FAIL: 0 | XFAIL: 2 | XPASS: 0

A full log can be found on karaba in '/tmp/dynare-master-check-XlCdr2hi2U.log'.