Latest OSE version variable introduced + example (#135)

Fixes: #133 

Introduced **ose_latest** variable, which is created from OSE github
repo metadata.

Author: mrgarris0n

Gemfile

@@ -100,6 +100,7 @@ gem "nokogiri"
 group :jekyll_plugins do
 
     gem "jekyll-remote-theme"
+	gem "jekyll-github-metadata"
     # gem "jekyll-paginate"
     # gem "jekyll-sitemap"
     # gem "jekyll-gist"

_config.yml

@@ -24,6 +24,7 @@ plugins:
   - jekyll-sitemap        # Jekyll plugin to silently generate a sitemaps.org compliant sitemap for your Jekyll site.
   - jekyll-gist 	        # Liquid tag for displaying GitHub Gists in Jekyll sites.
   - jekyll-include-cache  # Liquid tag that caches Liquid includes.
+  - jekyll-github-metadata
 
 # Whitelist plugins under safe mode.
 whitelist:
@@ -256,3 +257,5 @@ footer:
 product:
   name: 'syslog-ng Open Source Edition'
   short_name: 'syslog-ng OSE'
+
+repository: syslog-ng/syslog-ng

_includes/doc/common_snippets

@@ -12,6 +12,8 @@ that contains the include tag, further inherited e.g. layouts will not see the i
 
 {% assign img_folder = '/assets/images' | relative_url %}
 
+{% assign ose_latest = site.github.latest_release.name | remove: '.tar.gz' | remove: 'syslog-ng-' %}
+
 {% include doc/dev-guide/common_snippets %}
 
 {% include doc/admin-guide/common_snippets %}

doc/_admin-guide/README.md

@@ -2,8 +2,7 @@
 title: syslog-ng Open Source Edition Administration Guides
 id: adm-guide
 description: >-
-    Welcome to the {{ site.product.name }} 4.6 Administration Guide.
-    This document describes how to configure and manage {{ site.product.name }} ({{ site.product.short_name }}). Background information for the technology and concepts used by the product is also discussed.
+    Welcome to the {{ site.product.name }} {{ site.github.latest_release.name | remove: '.tar.gz' | remove: 'syslog-ng-'}} Administration Guide. This document describes how to configure and manage {{ site.product.name }} ({{ site.product.short_name }}). Background information for the technology and concepts used by the product is also discussed. 
 ---
 
 ## Target audience