Add Preprints page and navigation link

Author: MatrixCQY

_data/navigation.yml

@@ -11,6 +11,9 @@ main:
   - title: "Publications"
     url: /publications/
 
+  - title: "Preprints"
+    url: /preprints/
+
   - title: "Teaching"
     url: /teaching/    
 

_pages/preprints.md

@@ -0,0 +1,10 @@
+---
+layout: archive
+title: "Preprints"
+permalink: /preprints/
+author_profile: true
+---
+
+Coming soon...
+
+{% include base_path %}