Improve cli docstring (#240)

Author: max-sixty

README.md

@@ -51,7 +51,8 @@ cargo install prql
 ### Usage
 
 ```sh
-echo "from employees | filter has_dog" | prql compile
+$ echo "from employees | filter has_dog" | prql compile
+
 SELECT
   *
 FROM
@@ -60,7 +61,7 @@ WHERE
   has_dog
 ```
 
-More details in `prql compile --help`. See below for better examples of PRQL.
+See below for fuller examples of PRQL.
 
 ### Python implementation
 

src/cli.rs

@@ -12,13 +12,15 @@ enum Dialect {
 }
 
 #[derive(Parser)]
-#[clap(name = env!("CARGO_PKG_NAME"), about, version, author)]
+#[clap(name = env!("CARGO_PKG_NAME"), about, version)]
 pub enum Cli {
     Compile(CompileCommand),
 }
 
 #[derive(Args)]
-#[clap()]
+/// Compile a PRQL string into a SQL string.
+///
+/// See https://github.com/max-sixty/prql for more information.
 pub struct CompileCommand {
     #[clap(default_value="-", parse(try_from_os_str = Input::try_from))]
     input: Input,