Switch to use upstreamed LayerOptions implementation

lib/charms/hadoop.py

@@ -1,6 +1,6 @@
 from jujubigdata.utils import DistConfig
-from charms.layer import LayerOptions
+from charms import layer
 
 
 def get_dist_config():
-    return DistConfig(data=LayerOptions('hadoop-client'))
+    return DistConfig(data=layer.options('hadoop-client'))

lib/charms/layer.py

@@ -1,28 +0,0 @@
-import yaml
-
-
-class LayerOptions(dict):
-    """
-    Container for layer-specific options.
-
-    Each layer can define options that it accepts in its ``layer.yaml`` file.
-    These definitions are provided in [jsonschema](http://json-schema.org/)
-    format, which is the same format that Juju Action parameters are defined.
-
-    Each layer can then also set option values that other layers have defined.
-    The option values are validated at charm build time, and are made available
-    to the charm via this class as a dictionary.
-    """
-    def __init__(self, layer_name):
-        """
-        Load layer-specific options from ``layer.yaml``.
-
-        If the ``options`` section is not available in ``layer.yaml``, it
-        falls back to a separate YAML file based on the `layer_name`.
-
-        :param str layer_name: The name of the layer whose options we want.
-        """
-        super(LayerOptions, self).__init__()
-        with open('layer.yaml') as fp:
-            layer_yaml = yaml.safe_load(fp)
-        self.update(layer_yaml.get('options', {}).get(layer_name, {}))