Show line numbers in source code.
Make anchors work again and highlight the anchored line.
Format according to JSdoc style guidelines.
Fix for long numbers in line numbers column (up to 5 digits which should be enough).
Select source code only

Works on Chrome, FF, Opera, Safari, IE10+.
More info about compatibility: http://caniuse.com/#feat=user-select-none
Merge pull request #532 from tubalmartin/feature-show-linenumbers

Feature: Show linenumbers with working anchors and highlight anchored line.