theme: upgrade to latest v4.1 dev (talk front matter upgraded)

Also:

- Project and Custom widgets renamed (upgraded)
- Rearranges section positions and adds demo section to introduce
the template and help the user get started

content/home/talks.md

@@ -4,7 +4,7 @@
 
 widget = "pages"  # Do not modify this line!
 active = true  # Activate this widget? true/false
-weight = 30  # Order that this section will appear.
+weight = 70  # Order that this section will appear.
 
 title = "Recent & Upcoming Talks"
 subtitle = ""
@@ -28,7 +28,9 @@ subtitle = ""
     category = ""
     publication_type = ""
     exclude_featured = false
-  
+    exclude_past = false
+    exclude_future = false
+    
 [design]
   # Toggle between the various page layout types.
   #   1 = List