Repair GH repo page url view only to point to master as committed originally...

... in #89

Applies to #200

* I currently see no advantage of pointing the view url to the current `tree/HEAD` when clicking the url to go to GH during the import process. I do however see a disadvantage of not being able to traverse up their breadcrumb list and being locked into a specific commit hash
* Since the import process is probably dependent upon `/tree/HEAD` now leaving that alone
* Add `target="_blank"` to this url since we do this anyways with multiple entries and keeps that window/tab open for importing after checking with GH
* Fix white space issue with optional target after POST routine returns

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Tested in dev okay.