Some file icons for org-brain.

I don't know which ones I'll need, I added some random ones.

config.org

@@ -392,6 +392,12 @@ kind of resource links.
                         (all-the-icons-octicon "file-pdf"))
                        ((string-match "\\.cpp" link)
                         (all-the-icons-alltheicon "cplusplus"))
+                       ((string-match "\\.cs" link)
+                        (all-the-icons-alltheicon "csharp"))
+                       ((string-match "\\.java" link)
+                        (all-the-icons-alltheicon "java"))
+                       ((string-match "\\.lua" link)
+                        (all-the-icons-fileicon "lua"))
                        ;; [TODO] This will break http file links to header files.
                        ;; Use instead a more clever regex match
                        ((and (string-match "\\.h" link)