Add -C for --cargo-arg

Author: sourcefrog

NEWS.md

@@ -2,7 +2,7 @@
 
 ## Unreleased
 
-- Added: `--cargo-arg` allows passing arguments to cargo commands (check, build, and test), for example to set `--release` or `--features`.
+- Added: `--cargo-arg` (or `-C` for short) allows passing arguments to cargo commands (check, build, and test), for example to set `--release` or `--features`.
 
 - Improved: Works properly if run from a subdirectory of a crate, or if `-d` points to a
   subdirectory of a crate.

src/main.rs

@@ -123,7 +123,7 @@ struct Args {
     version: bool,
 
     /// additional args for all cargo invocations.
-    #[argh(option)]
+    #[argh(option, short = 'C')]
     cargo_arg: Vec<String>,
 
     // The following option captures all the remaining non-option args, to