archetypes: Default `projects` to empty array (#206 #340)

* default `projects` to empty array
* prevent projects button being generated when not required

archetypes/publication.md

@@ -34,7 +34,8 @@ selected = false
 # Projects (optional).
 #   Associate this publication with one or more of your projects.
 #   Simply enter the filename (excluding '.md') of your project file in `content/project/`.
-projects = [""]
+#   E.g. `projects = ["deep-learning"]` references `content/project/deep-learning.md`.
+projects = []
 
 # Links (optional).
 url_pdf = ""

archetypes/talk.md

@@ -25,7 +25,8 @@ selected = false
 # Projects (optional).
 #   Associate this talk with one or more of your projects.
 #   Simply enter the filename (excluding '.md') of your project file in `content/project/`.
-projects = [""]
+#   E.g. `projects = ["deep-learning"]` references `content/project/deep-learning.md`.
+projects = []
 
 # Links (optional).
 url_pdf = ""