Fixed NoMethodError #size

[joelmeyerhamme]

alias_sections.size fails when it is nil, which happens when the alias is in the root dir (alias: /somepage.html) because Array access returns nil if the start is more than one item of the end (http://stackoverflow.com/questions/3947002/how-does-ruby-handle-array-range-accessing). #drop does not have this irregularity (https://github.com/thoughtbot/til/blob/master/ruby/all-but-the-first-element-from-array.md).

[taringamberini]

+1 for merging into master.

Thanks @joelmeyerhamme your fix works like a charm! Tarin

[egladman]

+1

Works as expected. Good job @joelmeyerhamme