Order of the class parameters is refactored

Order of those parameters is changed
to follow Puppet Style Guide recommendation [0].
Moreover, it will allow to an user to find much faster
a variable in a list of variables.

[0]. https://docs.puppetlabs.com/guides/style_guide.html

Change-Id: I560d954fc6daf6eff6fac5b4d2b582d338986303

manifests/init.pp

@@ -1,10 +1,10 @@
 # == Class: github
 #
 class github(
-  $username,
   $oauth_token,
-  $project_username,
   $project_password,
+  $project_username,
+  $username,
 ) {
   include ::jeepyb
   include ::pip