bugfix for slashes in resource names

[joshfried-aws]

Issue #, if available: fix for #256

Description of changes: To fix this bug, we check the number of / in a key. If the key has > 2 matches, we assume its possibly a resource name that contains a slash in it. In this case, we try different combinations to include keys with / in them until we find a valid key, or else we return an error.

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