Fix compatibility with SQlite

Also fixes a bug in plume-models

plume-cli/src/main.rs

@@ -5,9 +5,9 @@ extern crate plume_models;
 extern crate rpassword;
 
 use clap::App;
-use diesel::{Connection, PgConnection};
+use diesel::Connection;
 use std::io::{self, prelude::*};
-use plume_models::DB_URL;
+use plume_models::{DB_URL, Connection as Conn};
 
 mod instance;
 mod users;
@@ -22,7 +22,7 @@ fn main() {
     let matches = app.clone().get_matches();
 
     dotenv::dotenv().ok();
-    let conn = PgConnection::establish(DB_URL.as_str());
+    let conn = Conn::establish(DB_URL.as_str());
 
     match matches.subcommand() {
         ("instance", Some(args)) => instance::run(args, &conn.expect("Couldn't connect to the database.")),