[perl #125642] LTA error message when an unknown type is used for hides/does/of/as/returns

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# New Ticket Created by  Rob Hoelz 
# Please include the string:  [perl #125642]
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For example:

    > my sub foo() returns Bar { }
    ===SORRY!=== Error while compiling <unknown file>
    Invalid typename
    at <unknown file>:1
    ------> sub foo returns⏏ Bar { }

While the line number is probably enough to figure out what's going on, having 
a little added information would be nice.