markdownify the changelog
Use newer `language-` class name prefix

This change makes it partly possible to use Jekyll+RedCarpet+Prism.js without using a plugin.

Another change will respect Jekyll's `pygments` configuration option and not render the code block using Pygments. Together, these two changes allow using prism.js with Jekyll out of the box.
Don't print deprecation warning if no arg is specified. Fixes #1041.
Update history to reflect fix of #1041.
Let Commander handle bad args after printing of deprecation warning. Fixes #1040.
Update history to reflect fix of #1040
Fix the index build with LSI
Merge pull request #1045 from mojombo/fix-lsi-build

Fix the index build with LSI. Fixes #1039.
Update history to reflect merge of #1045
rebase changelog
Merge pull request #1027 from benbalter/markdownify-changelog

Markdownify the changelog
I have weird preferences with filenames. Sorry, not sorry.
Fix up markdownified history file.
Clean up history file. Update it to reflect merge of #1027
Merge pull request #1037 from djui/patch-1

Add newer `language-` class name prefix to code blocks
Provide backwards-compatibility for change in #1037.
Update tests to be compliant with #1037.
Update history to reflect merge of #1037.
Check to make sure there is a toc_token before trying to use it. Fixes #1047
Merge pull request #1048 from mojombo/fix-toc-rdiscount

Check to make sure there is a toc_token before trying to use it.