There is a great article about the syntax highlighting in Drupal configuration by the DrupalOnWindows.com and I just want to make an addition to it.
Following steps described in it I wasn't able to see CodeSnippet button in CKEditor layout configuration for some reasons, it feels like there is a bug causing this in CKEditor module. I've discovered that using this plugin is possible with ease by using CDN version of CKEditor. Put the following
in the "Path to CKEditor" in "CKEditor Global profile" settings and the you will be able to enable CodeSnippet plugin for the CKEditor profile of your choice and put CodeSnippet plugin button in layout configuration.