Create a message queue

The create command creates a new message queue with support of the
typical parameters `mode`, `capacity` and `msgsize`. This command also
supports the global argument `verbose`.

src/cli.rs

@@ -1,3 +1,4 @@
+use crate::create::Create;
 use clap::{crate_authors, crate_version, AppSettings, Clap};
 
 #[derive(Clap, Debug)]
@@ -12,4 +13,11 @@ pub struct Opts {
     /// Produce verbose output
     #[clap(short, long, global = true)]
     pub verbose: bool,
+    #[clap(subcommand)]
+    pub command: Command,
+}
+
+#[derive(Clap, Debug)]
+pub enum Command {
+    Create(Create),
 }