Correct dive phase flip and my hackfix for it

[ryanjdillon]

I discovered the ascent/descent dive phases were flipped due to my forgetting the dive data were in positive values of depth (i.e. 5m not -5m). I made a hackfix for this when the output data from the glide identification were compiled, so as to not have to process the data again.

This should be fixed in glideid.py and then in smartmove/visuals/utils.py/compile_exp_data().

            # TODO hackfix, correcting for incorrectly assigned phases in
            # calc_glide_des_asc(), swap back
            n_sgls_des = len(sgls[sgls['dive_phase'] == 'ascent'])
            n_sgls_asc = len(sgls[sgls['dive_phase'] == 'descent'])
            #n_sgls_des = len(sgls[sgls['dive_phase'] == 'descent'])
            #n_sgls_asc = len(sgls[sgls['dive_phase'] == 'ascent'])