resolve: change most backwards incompatible ambiguity errors to `legacy_imports` warnings#38271

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bors merged 1 commit intorust-lang:masterfrom

jseyfried:rfc_1560_warning_cycle

Dec 20, 2016

Commits on Dec 15, 2016

Demote most backwards incompatible ambiguity errors from RFC 1560 to warnings.
jseyfried
committed