Description of proposed changes

This PR modifies readfile/writefile to read and write complex binary files (from isce-2) directly in complex data type by default.

For plotting in view.py, which requires real data type, I add readfile.get_slice_list(no_complex) option to translate complex into mag/phase for plotting. This option is turn off by default for generic I/O.

• readfile:

  • read_binary_file(): for "slc", set cpx_band to "complex" unless mag/phase is clearly specified.
  • get_slice_list(): 1) ignore meaningless geo/rdr file extension; 2) add "no_complex" arg to switch between complex (for I/O) and mag/phase (for plotting)

• writefile:

  • write(): for .slc/.int, write complex directly
  • write_isce_xml(): add "image_type" arg to initiate different ISCE-2 image objects for better compatiability
  • write_isce_file(): support file_type == 'isce_slc'
  • comment out obsolete write_complex64() as write_complex_float32() is equivalent but simpler and faster.

• subset/multilook: update usage of writefile.write_isce_xml()

• view: update usage of readfile.get_slice_list()

Other minor changes:

• subset.py: add --sub-x/y/lat/lon and --subset-x/y/lat/lon to be consistent with subset option names in other scripts.
• view.py: add --nmli / --num-multilook for --multilook-num
• simulation.simulation.py: typo fix and add missing wvl arg while calling timeseries2ifgram()
• objects.sensor: typo fix for doppler_bandwidth

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