Some small corrections

 * Fixed an unsightly typo on the "WeakSet#add returns this" test.
 * Fixed a few results for Node Harmony and Chrome.
Merge pull request #321 from webbedspace/shameful-fixes

Some small corrections
Rework header
Fixed some WebKit Map/Set test results.
Merge pull request #325 from webbedspace/webkit

Fixed some WebKit Map/Set test results.
Try to update damn flattr buttons again
And another flattr fix
Fix flattr once and for all
Remove index.html, update compilers’ results
Added an "instances of iterables" subtest to for-of.
Added extra yield * tests.

Also:
 * Extended the 'instances of iterables' tests to the other iterator-consuming syntaxes.
 * Abstracted the test code for creating a generic iterable into a __createIterableObject function, which is included in all ES6 skeleton files and the Node test script. This is something of a readability trade-off: sacrificing transparency for clarity and brevity.
Updated yield * results for various browsers.

Also:
 * Fixed a bug which caused the for-loop strict tests to crash in Chrome 38.
 * Fixed some mistakes in the Set results for Firefox.
Merge pull request #326 from webbedspace/iterable-instances

Added iteration tests for instances of iterables
Try adding gittip buttons
Tweak buttons position
Removed Gratipay button for webbedspace

I currently don't have a Gratipay account, so this button has no purpose.

Also cleaned up some whitespace in data-es6.js while I was at it.