Make the container build instructions more reproducible

Add --distribution so that it will use the .lock file contents,
otherwise with the latest fedora:latest container it fails with a bunch
of complaints.

Add vendor to the _config.yml so that jekyll doesn't think it's part of
your site and try to parse things it shouldn't.

Author: brlane-rht

.gitignore

@@ -8,3 +8,4 @@ Gemfile
 Gemfile.lock
 node_modules
 package.json
+vendor

StyleGuide.md

@@ -9,7 +9,7 @@ your user id (so that you can edit from within the container without making ever
 
     sudo docker build -t weldr/jekyll .
     sudo docker run -it --name=jekyll --security-opt="label=disable" -v "$PWD:/weldr.io/" --env LOCAL_UID=`id -u` -p 4000:4000 weldr/jekyll /usr/bin/bash
-    bundle install --binstubs=/tmp/bin/
+    bundle install --binstubs=/tmp/bin/ --deployment
     bundle exec /tmp/bin/jekyll serve --host=0.0.0.0 --incremental
 
 ...then just open http://localhost:4000/ and you're off. On subsequent runs you can reuse the container with:

_config.yml

@@ -89,5 +89,6 @@ exclude:
   - README.md
   - CNAME
   - StyleGuide.md
+  - vendor
 
 theme: jekyll-theme-hacker