Adding tick/tock scripts for performance measuring
Added es5-shim, so we can use ecmascript 5 (Object.create,
Array.isArray) without breaking older browsers.
Merge pull request #10 from eob/performance-measuring

Adding tick/tock scripts for performance measuring
Merge pull request #13 from karger/2013-07-22_ecmascript5

- Moving database to hash of hashes (constant time lookup) isntead of hash of arrays.
- Shim for some ECMA Script 5 features on common data containers.