updated install_d2.sh

setup/install_d2.sh

@@ -27,6 +27,8 @@ Installs the D2 diagram scripting language
     https://d2lang.com/
 
     https://github.com/terrastruct/d2/blob/master/docs/INSTALL.md
+
+    https://github.com/terrastruct/tala#installation
 "
 
 # used by usage() in lib/utils.sh
@@ -41,6 +43,9 @@ help_usage "$@"
 
 curl -fsSL https://d2lang.com/install.sh | sh -s --
 
+# Install proprietary Tala layout engine too
+curl -fsSL https://d2lang.com/install.sh | sh -s -- --tala
+
 # can also install via go but won't get the man page
 #
 # go install oss.terrastruct.com/d2@latest