Revert "[BEAM-2005] Move getScheme from FileSystemRegistrar to FileSy…

[tgroh]

…stem"

This reverts commit ce88c88.

Be sure to do all of the following to help us incorporate your contribution
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  [BEAM-<Jira issue #>] Description of pull request
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[tgroh]

@lukecwik

[tgroh]

#2675 also solves this

[coveralls]

Coverage decreased (-0.008%) to 69.676% when pulling 25f9b4a on tgroh:revert_getscheme_fs_registrar into a8a04a2 on apache:master.