Added DoWaitForElement command

Also added a Wait bool to the base selector command so any selector
based command can optionally wait for the element to exist, up to the
specified timeout.
Merge pull request #2 from InfinitiesLoop/master

Added DoWaitForElement command
Added Wait feature to the multi-selector command

Also changed how default timeout is set so the value can remain 0 for
benefit of json serializing without default values.
Merge pull request #3 from InfinitiesLoop/master

Added Wait feature to the multi-selector command
Show more info when things fail

And don't serialize default values when serializing manifests, etc.
Merge pull request #4 from InfinitiesLoop/master

Show more info when things fail
Merge remote-tracking branch 'origin/master' into TestResultTreeView

Conflicts:
	Selenite.Tests/TestScripts/DoCommands.json
	Selenite/packages.config