Sorting collections in Liquid templates03 April 2013
Sorting in Jekyll looks quiet simple with standard Liquid Filters
sort, but it did not worked out.
Because Liquid converts ruby hashes to arrays, e.g the Jekyll variables beneath site, like categories and tags (e.g. site.tags):
for tag in site.tags <li></li> endfor
e.g. site.tags will be converted to an array of tuples in which  refers to the key and  to the list of values. Without monkey patching you can not sort the tuples alphabetically by the key  of each of them - very sad!