implement posting in the past with published flag

src/microcosm/__init__.py

@@ -7,6 +7,8 @@ import giteapy
 import giteapy.rest
 import time
 import base64
+
+
 from werkzeug.datastructures import FileStorage
 import yaml
 
@@ -321,6 +323,12 @@ def process_json_post():
     props = body['properties']
     entry_type = detect_entry_type(props)
 
+    if 'published' in props:
+
+        from dateutil import parser
+        
+        now = parser.parse(props['published'][0])
+    else:
         now = datetime.now()
 
     frontmatter, file_path = init_frontmatter(now, entry_type, props.get('name'))