Add builds enabled option to config.sh

First discovered in GitLab 8.2.2-ee on GitLab.com.

When creating new projects builds, will are now enabled by default. This should be exposed as an option in config.sh.

diff --git a/lib/manage_gitlab_project.py b/lib/manage_gitlab_project.py
index ac8accf..7c8ec82 100755
--- a/lib/manage_gitlab_project.py
+++ b/lib/manage_gitlab_project.py
@@ -70,6 +70,7 @@ def createproject(pname):
     'snippets_enabled': options.snippets,
     'public': options.public,
     'namespace_id': git.find_group(name=gitlab_namespace).id,
+    'builds_enabled': False
   }
   #make all project options lowercase boolean strings i.e. true instead of True
   for x in project_options.keys():

The config.sh option could be

builds_enabled=true

The default value should be false if config.sh doesn't contain it.