docs: update term "program"

docs/developer-guide.md

@@ -4,18 +4,17 @@ This page gives insights on extending Aura Engine internals or through the API.
 
 <!-- TOC -->
 
-1. [Aura Engine Development Guide](#aura-engine-development-guide)
-   1. [AURA Components](#aura-components)
-   2. [Engine Components](#engine-components)
-   3. [Running for Development](#running-for-development)
-   4. [Testing](#testing)
-   5. [API](#api)
-   6. [Scheduler](#scheduler)
-   7. [Daemonized Engine](#daemonized-engine)
-      1. [Running with Systemd](#running-with-systemd)
-      2. [Running with Supervisor](#running-with-supervisor)
-   8. [Logging](#logging)
-   9. [Read more](#read-more)
+1. [AURA Components](#aura-components)
+2. [Engine Components](#engine-components)
+3. [Running for Development](#running-for-development)
+4. [Testing](#testing)
+5. [API](#api)
+6. [Scheduler](#scheduler)
+7. [Daemonized Engine](#daemonized-engine)
+   1. [Running with Systemd](#running-with-systemd)
+   2. [Running with Supervisor](#running-with-supervisor)
+8. [Logging](#logging)
+9. [Read more](#read-more)
 
 <!-- /TOC -->
 
@@ -31,7 +30,7 @@ For example:
 
 - Steering, to get the main incredient of an play-out engine: schedules (or "timeslots" in Steering terms),
   which hold the actual information on playlists and their items.
-- Dashboard, to have a neat interface, being able to programme the timeslots
+- Dashboard, to have a neat interface, being able to program the timeslots
 - Tank, to get the references to audio files and other audio sources. Plus the actual files.
 
 If you need to test and develop against the Engine's API you'll also need to get the `engine-api` project running.