Sort plugins so people can have "load orders".

This allows for people to do something like "_plugins/1-autoload-global.rb" and have it load first and so on making it much easier to organize code and have a "header file" that does all the requiring up front if it's needed for all plugins.
Remove trailing whitespace
Pagination generator should have :lowest priority
Merge pull request #1759 from mojombo/pagination-lowest-priority

Pagination generator should have :lowest priority
Update history to reflect merge of #1759
Prep for the 1.3.1 release
Release 1.3.1
Update the gemspec with the release post
fix wrong case for a word
Parse TOML or YAML in Jekyll::Configuration.
Better config file parser error if it's not there.
Give that LoadError a good message.
require the TOML gem, idiot.
Add some unit tests for TOML integration.
add a space between "find" and "an"
Merge pull request #1769 from davidsawyer/master

add a space between "find" and "an"
Update history to reflect merge of #1769
Merge pull request #1755 from gregkare/more_trailing_whitespace

Remove trailing whitespace
Update history to reflect merge of #1755
Merge pull request #1762 from yizeng/master

fix wrong case for a word