Config file format

[ceholden]

Switch config file format to YAML. Primary reason for change is that YAML can automatically parse the data types in the config files. This saves me a lot of coding, is more flexible since I don't have to update a parser, and is probably gives the user more flexibility in the long term.

Target release v0.5.0 since that one doesn't work with existing config files anyway. Why update your config files for v0.5.0 only to also port to YAML in the future?

Example:

metadata:
    version: "0.5.0"

dataset:
    # Text file containing dates and images
    input_file: "/home/ceholden/Documents/yatsm/examples/p022r049_input.csv"
    # Input date format
    date_format: "%Y%j"
    # Output location
    output: "/home/ceholden/Documents/landsat_stack/p022r049/images/YATSM"
    # Output file prefix (e.g., [prefix]_[line].npz)
    output_prefix: "yatsm_r"
    # Total number of bands
    n_bands: 8
    # Mask band (e.g., Fmask)
    mask_band: 8
    # List of integer values to mask within the mask band
    mask_values: [2, 3, 4, 255]
    # Valid range of non-mask band data
    # specify 1 range for all bands, or specify ranges for each band
    valid_range: [0, 10000]
    # Indices for multi-temporal cloud masking (indexed on 1)
    green_band: 2
    swir1_band: 5
    # Use BIP image reader? If not, use GDAL to read in
    use_bip_reader: true
    # Directory location for caching dataset lines
    cache_line_dir: "/home/ceholden/Documents/landsat_stack/p022r049/images/.yatsm_cache"

produces:

In [8]: cfg = yaml.safe_load(open('p022r049_example.yaml'))

In [9]: cfg
Out[9]: 
{'dataset': {'cache_line_dir': '/home/ceholden/Documents/landsat_stack/p022r049/images/.yatsm_cache',
  'date_format': '%Y%j',
  'green_band': 2,
  'input_file': '/home/ceholden/Documents/yatsm/examples/p022r049_input.csv',
  'mask_band': 8,
  'mask_values': [2, 3, 4, 255],
  'n_bands': 8,
  'output': '/home/ceholden/Documents/landsat_stack/p022r049/images/YATSM',
  'output_prefix': 'yatsm_r',
  'swir1_band': 5,
  'use_bip_reader': True,
  'valid_range': [0, 10000]},
 'metadata': {'version': '0.5.0'}

Pretty great!