Switch to ctest crate

Extracted tests!
diff --git a/libc-test/src/lib.rs b/libc-test/src/lib.rs
deleted file mode 100644
index e69de29..0000000
--- a/libc-test/src/lib.rs
+++ /dev/null
diff --git a/libc-test/src/main.rs b/libc-test/src/main.rs
new file mode 100644
index 0000000..e4cb8fe
--- /dev/null
+++ b/libc-test/src/main.rs
@@ -0,0 +1,6 @@
+#![allow(bad_style)]
+extern crate libc;
+
+use libc::*;
+
+include!(concat!(env!("OUT_DIR"), "/all.rs"));