Updated IO docs so the modules appear better

Fixed 2531308.

Update 2531037 -- add object to string serialisation, for upload requests, in io-upload-iframe.

Fixed 2531041.

Reinstate code changes This is a revert-revert. Code changes made on the 3.4.0+ branch were reverted on the branch, then this revert commit merged into master (since all commits on 3.4.0+ should be documentation, a blanket merge should be safe), which then reverted the code changes where they were appropriate. Short form: this commit allows blanket merges from 3.4.0+ onto master again at the expense of some git log history confusion for IO. This reverts commit 9075924bcea60fa6f20409922beab1573624fd2d.

Revert code changes. This reverts commit fae935a1d05f42297080eb819044d733326dd613.

Fixed 2530999. Fixed 2531037. Fixed 2531038.

s/tabs/spaces/ and other API doc tweaks Things like {object} or {o} => {Object}

IO API Doc updates only. No code changes.

Fix incorrect IO reference from conn to io, in response object.

Fixed missing semi-colon errors per JSLint.

Source for implementing 2530370, 2529447, 2529314, 2530373.

Fix 2529553. Original fix did not correctly revert the HTML form attribute values to their pre-upload state.

Gabe Moothart's pull request to fix 2529610.

Fix #2529553.

Fix #2529546. Key and value strings are subject to decodeURIComponent in the event the data are already encoded (e.g. querystring-stringify).

Update enctype attribute logic to account for IE9.

Refactor code to correct JSLint "undefined function" warnings. Note: diffs will be large due to code reordering.

Fixed #2528646

Fixed 2528685.

Fixed doc error for _resetAttr.

Fixed 2528063 and implemented 2528024.

Added native XDR support, XML response for XDR transactions, and dependency optimizations.

Add explicit px unit declaration to iframe style definitions.

Update io-base.js to synchronize with io-xdr.js when calling isInProgress for cross-domain transactions. Removed redundant semi-colons from all io sub-modules.

Fixed #2525999 and #2527819

Restructured source files and directory structure for YUI3.