Some more attributes to ignore for IE7
`wymEqual`: don't parse HTML by default.
prepareDocForEditing adds a `br` to empty documents.
Revert "prepareDocForEditing adds a `br` to empty documents."

This reverts commit b3497b3499b92df071d2da83014dae5468946bb9.
All browsers are now double_br_browsers.
testWym general testing utility.
Revert "Revert "prepareDocForEditing adds a `br` to empty documents.""

This reverts commit 1ebc7a213dc29e1e1d1edc3ca257e98d7711b1c4.
`normalizeHtml` attributes kept by whitelist instead of blacklist
Fix table row merging.
Make jshint happy.
Fix a paste test.
Fix an image insertion test.
Don't expect IE to randomly add whitespace in some test.
Fix some table tests.
Fix a structured headings test.
Fix _selected image is saved on mousedown test.
Call `prepareDocForEditing` from `rawHtml`, not `update`.
Fix typo in api docs.
Fixed typo in IRC address
Merge pull request #617 from kylegibson/patch-1

Fixed typo in IRC address