(fix) fail! to panic!
Merge pull request #4 from reem/fix/fail-to-panic

(fix) fail! to panic!
(fix) Error::erase was removed due to new trait object safety rules.
Merge pull request #3 from iron/fix/no-error-erase

(fix) Error::erase was removed due to new trait object safety rules.
(chore) Update travis and clean warnings.