:bug: Track file with empty lines

[jamal919]

Any JTWC track file with empty line throws an error saying -

Traceback (most recent call last):
  File "build_sflux.py", line 24, in <module>
    track = read_jtwc('track_rsmc.csv')
  File "/home/khan/MEGA/Codes/pyschism/schism/io.py", line 76, in read_jtwc
    ncyclone = int(fields[1].strip())
IndexError: list index out of range

Possible fixes are checking for empty lines and exclude them.