Fleshed out exception handling.  Improved resource management.
Created a CreateInternal method on Document to avoid an extra null argument check.
Previewurl document element renamed to previewlink.  Fixed bug where StartTag search parameter wasn't being properly set in the HttpSearchCommand class.
Merge remote-tracking branch 'origin/master' into Development
Merge remote-tracking branch 'origin/master' into Development
Removed virtual modifier from Hits property on SearchHitCollection.
Fixed bug where HttpActionCommand cannot be invoked twice because the Action parameter would be added twice to the parameters dictionary, causing an exception to be thrown.