CLI tools

- New sub-crate: plume-cli
- Creates a binary called 'plm'
- Uses clap to parse CLI arguments
- Add a first command: plm instance new (to init the local instance)

plume-cli/src/main.rs

@@ -0,0 +1,37 @@
+extern crate clap;
+extern crate diesel;
+extern crate dotenv;
+extern crate plume_models;
+
+use clap::App;
+use diesel::{Connection, PgConnection};
+use std::io::{self, Write};
+use plume_models::DB_URL;
+
+mod instance;
+
+fn main() {
+    let mut app = App::new("Plume CLI")
+        .bin_name("plm")
+        .version("0.2.0")
+        .about("Collection of tools to manage your Plume instance.")
+        .subcommand(instance::command());
+    let matches = app.clone().get_matches();
+
+    dotenv::dotenv().ok();
+    let conn = PgConnection::establish(DB_URL.as_str());
+
+    match matches.subcommand() {
+        ("instance", Some(args)) => instance::run(args, &conn.expect("Couldn't connect to the database.")),
+        _ => app.print_help().unwrap()
+    };
+}
+
+pub fn ask_for(something: &str) -> String {
+    write!(io::stdout(), "{}", something).ok();
+    write!(io::stdout(), ": ").ok();
+    let mut input = String::new();
+    io::stdin().read_line(&mut input).expect("Unable to read line");
+    input.retain(|c| c != '\n');
+    input
+}