Rename `Zero` variant to `NoSign`
Merge pull request #3 from japaric/rename-zero

Backport: Rename `Zero` variant to `NoSign`
Add a README for num
Merge pull request #4 from steveklabnik/master

Add a README for num
Convert statics to constants
Fix `non_uppercase_statics` warnings of private constants.
Migrate to new `cfg` attribute syntax`
Merge pull request #16 from gifnksm/master

Convert statics to constants
Update to Rust master

Closes #17
fail -> panic
Merge pull request #18 from zsiciarz/master

fail -> panic
Fix warning about renamed missing doc attribute.
Merge pull request #19 from jbcrail/fix-missing-doc-warning

Fix warning about renamed missing doc attribute.