Add more logging to flamingo so that the logs record progress.

[agstephens]

E.g. you get this in the job-error.txt but no information for the user via the WPS:

[root@ceda-wps-staging ~]# more /gws/nopw/j04/ceda_wps/birds/test/tmp/flamingo/pywps_process_7h_sxp9v/job-error.txt
/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/ceda_wps_assets/flamingo.py:13: YAMLLoadWarning: calling yaml.load() without Loader=..
. is deprecated, as the default Loader is unsafe. Please read https://msg.pyyaml.org/load for full details.
  resp = yaml.load(open(dset_assets_file))
Traceback (most recent call last):
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/file_manager.py", line 199, in _acquire_with_cache_info
    file = self._cache[self._key]
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/lru_cache.py", line 53, in __getitem__
    value = self._cache[key]
KeyError: [<function _open_scipy_netcdf at 0x2ab67e407950>, ('/badc/cru/data/cru_ts/cru_ts_4.05/data/wet/cru_ts4.05.1901.2020.wet.dat.nc.gz',), 'r',
 (('mmap', None), ('version', 2))]

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/pywps/app/Process.py", line 250, in _run_process
    self.handler(wps_request, wps_response)  # the user must update the wps_response.
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/flamingo/processes/wps_subset_cru_ts.py", line 161, in _handler
    results = subset(**inputs)
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/daops/ops/subset.py", line 77, in subset
    result_set = Subset(**locals()).calculate()
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/daops/ops/base.py", line 35, in __init__
    self._consolidate_collection()
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/daops/ops/base.py", line 54, in _consolidate_collection
    self.collection, time=self.params.get("time")
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/daops/utils/consolidate.py", line 58, in consolidate
    ds = open_xr_dataset(dset)
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/roocs_utils/xarray_utils/xarray_utils.py", line 42, in open_xr_dataset
    dset[0], use_cftime=True, decode_timedelta=False, **kwargs
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/api.py", line 505, in open_dataset
    **kwargs,
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/scipy_.py", line 281, in open_dataset
    decode_timedelta=decode_timedelta,
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/store.py", line 22, in open_dataset
    vars, attrs = store.load()
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/common.py", line 125, in load
    (_decode_variable_name(k), v) for k, v in self.get_variables().items()
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/scipy_.py", line 167, in get_variables
    (k, self.open_store_variable(k, v)) for k, v in self.ds.variables.items()
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/scipy_.py", line 156, in ds
    return self._manager.acquire()
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/file_manager.py", line 181, in acquire
    file, _ = self._acquire_with_cache_info(needs_lock)
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/file_manager.py", line 205, in _acquire_with_cache_info
    file = self._opener(*self._args, **kwargs)
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/xarray/backends/scipy_.py", line 81, in _open_scipy_netcdf
    gzip.open(filename), mode=mode, mmap=mmap, version=version
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/scipy/io/netcdf.py", line 279, in __init__
    self._read()
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/scipy/io/netcdf.py", line 608, in _read
    self._read_var_array()
  File "/usr/local/anaconda/envs/flamingo/lib/python3.7/site-packages/scipy/io/netcdf.py", line 720, in _read_var_array
    dtype=dtypes).copy()
MemoryError: Unable to allocate 2.78 GiB for an array with shape (1440,) and data type [('time', '>f4'), ('wet', '>f4', (360, 720)), ('stn', '>i4',
(360, 720))]