Add sinon.assert.match

Makes it possible to use the Sinon matcher API on arbitrary data,
without a spy having been called.
Add test for sinon.assert.match
remove sandbox injected properties on restore
added tests
Add test for assert.match failure message
Fix onload call, 'this' should be equal to XHR object
Merge pull request #411 from lusini/Remove-sandbox-injected-values-on-restore

Remove sandbox injected values on restore
More specific feature test for ProgressEvent

Avoids IE11 bug, where ProgressEvent is not callable with new. Fixes #409
Check for ProgressEvent support but use sinon.Event

Avoids IE/host object problems while maintaining browser support semantics.
Merge pull request #422 from NAndreasson/fix/onload-this

Fix onload call, 'this' should be equal to XHR object
Merge pull request #410 from ropez/master

Add sinon.assert.match
prevent setRequestHeaders from being called twice
Merge pull request #424 from fearphage/fix-402/fake-xhr-compliance

Prevent setRequestHeaders from being called twice (like setRequestBody)
Added ProgressEvent and CustomEvent to sinon.Event. This will fake the original events in the fake xhr. Fixes issue #409.
Merge branch 'master' of https://github.com/gtothesquare/Sinon.JS