Add wait-for-them (#514)

* Add wait-for-them

* add to glibc_pre_2_34_incompat

* ignore --help/--version check

* update markdown

tools/codegen/base/wait-for-them.json

@@ -0,0 +1,13 @@
+{
+  "repository": "https://github.com/shenek/wait-for-them",
+  "license_markdown": "[GPL-3.0](https://github.com/shenek/wait-for-them/blob/master/Cargo.toml#L7)",
+  "tag_prefix": "v",
+  "rust_crate": "${package}",
+  "asset_name": "${package}-${rust_target_os}${exe}",
+  "version_range": ">= 0.4.0",
+  "platform": {
+    "x86_64_linux_gnu": {},
+    "x86_64_windows": {},
+    "aarch64_macos": {}
+  }
+}