Added rough draft of 2.2.1 changelog
Updating WYSIWYG field type docs.

Adding notes on Allow Tags, and other clarifications.
Updating textarea field type docs.
Changelog revisions.
Adding documentation of redirect function.
Link to textarea field type with new options.
Removing this. This isn't in this version.
escaped underscores. because markdown.
Fixed two formatting errors
Merge branch '2.2' of https://github.com/pyrocms/pyrocms-docs into 2.2