Use rucksack to embed known runtimes in the binary

src/commands/new.cr

@@ -1,12 +1,26 @@
+require "rucksack"
+
 module Faaso
   module Commands
     # Creates a new empty funko out of a given runtime
     struct New
+      @@known : Array(String) = {{`find ./runtimes -type d -mindepth 1`.split('\n').reject(&.empty?)}}
+
       def run(options, folder)
-        if options["RUNTIME"].as(String) == "list"
-            Log.info {"Known runtimes:"} 
+        if options["-r"].as(String) == "list"
+          Log.info { "Crystal has some included runtimes:\n" }
+          @@known.each do |runtime|
+            Log.info { "  * #{Path[runtime].basename}" }
+          end
+          Log.info { "\nOr if you have your own, use a folder name" }
+          return 0
         end
       end
     end
   end
 end
+
+# Embed runtimes in the binary using rucksack
+{% for name in `find ./runtimes -type f`.split('\n') %}
+  rucksack({{name}})
+{% end %}