Refactor update creation api

This merge request does the following:

• Raise DRF errors rather than returning response to take advantage of the DRF exception handling mechanism
• Create serialisers for PUT request to simplify the code
• Improve validation checks in several places
• Fixes several issues in DRF infrastructure uses
• Fixes JSON fields handling
• Remove routes that do no fully qualify objects
• Implement a custom DRF exception handler that will allow to log errors
• Improve testing
• Improve permission management

beat/web/common/serializers.py

@@ -41,6 +41,7 @@ from ..team.models import Team
 from ..common.utils import ensure_html
 from ..common.utils import annotate_full_name
 from ..common.utils import validate_restructuredtext
+from ..common import fields as beat_fields
 
 from .models import Shareable, Versionable, Contribution
 from .exceptions import ContributionCreationError
@@ -301,7 +302,7 @@ class ContributionSerializer(VersionableSerializer):
 
 
 class ContributionModSerializer(serializers.ModelSerializer):
-    declaration = serializers.JSONField(required=False)
+    declaration = beat_fields.JSONField(required=False)
     description = serializers.CharField(required=False, allow_blank=True)
 
     class Meta: