Updating Using local tgz and MD5

[JRGonz]

When trying to update using the -u file:// -s file:// the md5 checksum fails because the filename changes with regard from the checksum.

ex: If I am trying to update from a file named platform-20190812T165055Z.tgz then the md5sum.txt I has to be:

4878c946cf49ecad108be99fecf9c8fb platform-release--20190812T165055Z.tgz

release-- is added to what the script looks for.

The expected behavior would be that the md5sum.txt would have the actual filename in it. This threw me off quite a bit when trying to update from a tgz.