compacter timing

[remodietlicher]

all times on one line and added speedup report, eg:

                                                    reference  current   speedup
routine                                                                         
radiation_mcica_lw:solver_mcica_lw                     0.3870    5.710  0.067776
radiation_lw_derivatives:calc_lw_derivatives_ica       0.0242    0.153  0.158170
radiation_cloud_generator:cloud_generator              0.0975    0.110  0.886364
radiation_adding_ica_lw:calc_fluxes_no_scatteri...     0.0721    0.136  0.530147
radiation_lw_derivatives:modify_lw_derivatives_ica     0.0337    0.082  0.410976
radiation_adding_ica_lw:fast_adding_ica_lw             0.0833    0.911  0.091438