Update docs for -r feature of branch command

Update docs for -r feature of branch command so that it is clearer that
it pushes up the branch to the remote.

<!-- ps-id: 27d45cfb-f02b-476e-b696-2d3315c3c699 -->

src/cli.rs

@@ -23,7 +23,7 @@ pub struct BranchCmdOpts {
     /// Use the provided branch name instead of generating one
     #[structopt(short = "n")]
     pub branch_name: Option<String>,
-    /// Create a remote branch of the same name
+    /// Create a remote branch of the same name and push
     #[structopt(short = "r")]
     pub create_remote_branch: bool,
 }