Remove journal from required elements in reference field

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Conda builds are now noarch - one package for all Pythons!
 - pip installs now require Python compatible with 3.5
 - Appveyor runs a single job and no longer builds conda packages
+- Remove journal from required fields in the reference
 
 ## [0.2.1] - 2017-08-31
 ### Fixed

pyked/schemas/chemked_schema.yaml

@@ -57,7 +57,6 @@ reference:
       min: 0
       type: integer
     journal:
-      required: true
       type: string
     doi:
       type: string

pyked/tests/test_validation.py

@@ -375,7 +375,7 @@ def test_missing_required_field(self, field, properties):
         assert v.errors[field][0] == 'required field'
 
     @pytest.mark.parametrize("field, sub", [
-        ('reference', 'authors'), ('reference', 'journal'), ('reference', 'year'),
+        ('reference', 'authors'), ('reference', 'year'),
         ('apparatus', 'kind'), ('file-author', 'name'),
     ])
     @pytest.mark.parametrize("properties", ['testfile_required.yaml'], indirect=["properties"])

pyked/tests/testfile_required.yaml

@@ -6,7 +6,6 @@ chemked-version: 0.0.1
 reference:
   authors:
     - name: A. Author
-  journal: Testing Journal
   year: 1600
 experiment-type: ignition delay
 apparatus: