Merge pull request #50 from mikofski/datalayer_args

refactor layers to remove redundancy
* layers are plural: `Calculations`, `Simulations`, `Formulas`, except `Data` layer
* layers are made from sources
* sources are singular: `Calc`, `Simulation`, `Formula`, except `DataSource`
* add `add()`, `edit()` and `delete()` methods to superclass
* add `reg_cls` class attirbute to super class, to be set by subclasses
* add `sources`, `reg` and `objects` to superclass

Author: mikofski

.gitignore

@@ -5,6 +5,7 @@
 .pydevproject
 .settings/
 .idea/
+.spyderproject
 
 # build
 *.pyc

carousel/core/__init__.py

@@ -5,7 +5,7 @@
 calculators, simulations is accomplished by sub-classing the appropriate
 class.
 
-The built-in classes are organized into 5 sections, which make up the layers
+The built-in classes are organized into 5 categories, which make up the layers
 of a model.
 
 * Data

carousel/core/formulas.py

@@ -57,7 +57,7 @@ def import_formulas(self):
         """
         This method must be implemented by each formula importer.
 
-        :returns: Formulas.
+        :returns: formulas
         :rtype: dict
         :raises: :exc:`~exceptions.NotImplementedError`
         """