Vendor dependencies

Let's see how I like this workflow.

vendor/xdg/Cargo.toml

@@ -0,0 +1,28 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+name = "xdg"
+version = "2.4.1"
+authors = ["Ben Longbons <b.r.longbons@gmail.com>", "whitequark <whitequark@whitequark.org>"]
+description = "A library for storing and retrieving files according to XDG Base Directory specification"
+homepage = "https://github.com/whitequark/rust-xdg"
+documentation = "https://docs.rs/xdg/"
+readme = "README.md"
+keywords = ["linux", "configuration"]
+license = "Apache-2.0/MIT"
+repository = "https://github.com/whitequark/rust-xdg"
+
+[lib]
+doctest = false
+[dependencies.dirs]
+version = "4.0"