Remove instructions to install source tree

Author: tomclose

_sessions/c1prep/3_github_account.md

@@ -1,5 +1,5 @@
 ---
-title: git & GitHub
+title: GitHub
 ---
 
 Git is a program that helps with the management of code. It means that you completely avoid the situation where you end up with files called `team_contacts_v1`, `team_contacts_v2` etc. It also allows you to share your code with others and collaborate on code in an efficient way.
@@ -8,11 +8,6 @@ GitHub is a site that makes sharing code part of git really easy. It is the go-t
 
 GitHub also allows you to put a static website online for free, using [GitHub Pages](http://pages.github.com/). We will be making use of this feature during the course.
 
-### SourceTree
-
-git itself is the sort of program that you have to run by typing commands into your computer's command line. At some point, you will need to know how to do this but, for the time being, we're going to use a *git client* - an point-and-click application to make git easier. In particular, we're going to be using a free git client called SourceTree. Downloading SourceTree will install both the git command line progam and the point-and-click application.
-
 {% exercise %}
-1. Sign up for a GitHub account at [https://github.com/](https://github.com/). Make sure you **know your password** to avoid awkward moments in class!
-2. Download [SourceTree](http://www.sourcetreeapp.com/) for Windows or Mac. If you're using linux, contact your course instructor.
-{% endexercise %}
+Sign up for a GitHub account at [https://github.com/](https://github.com/). Make sure you **know your password** to avoid awkward moments in class!
+{% endexercise %}