Add failing test for issue #624

Add a test to show that useFakeTimers is idempotent when it comes to the impact on Date.now
Freeze formatio dependency to 1.1.1 to allow tests to continue working

formation 1.1.2 introduces "(empty string)" as special formatting of
empty strings, which is a breaking change and should really be 1.2.0

However, right now we just need to have the tests passing so people
can keep working on **this** codebase.
Merge pull request #625 from mroderick/issue-624

Add failing test for issue #624
Merge pull request #626 from mroderick/freeze-formatio-dependency

Freeze formatio dependency to 1.1.1 to allow tests to continue working
1.12.2
Enable failing test
Changelog for 1.12.2
Tidy up the code in issues.js
Merge branch 'master' of https://github.com/GCheung55/Sinon.JS into wrap-ie