update recipes

recipes/wip/sheldon/recipe.toml

-#TODO Not compiled or tested
+#TODO libssh2-sys crate error
 [source]
 git = "https://github.com/rossmacarthur/sheldon"
 rev = "9a56dcfc79c6e9f9bcf8480c162c50db013bb172"

recipes/wip/shellfirm/recipe.toml

@@ -3,4 +3,7 @@
 git = "https://github.com/kaplanelad/shellfirm"
 rev = "0587f023a1d6b58e9fdb71d9a4e8d5460ee33c77"
 [build]
-template = "cargo"
+template = "custom"
+script = """
+cookbook_cargo_packages shellfirm
+"""