Remove zipper, async, temp deps, replace with node-zip.
Remove unneeded apt-get lines from travis.yml.
Remove 0.11 from travis.yml until libxmljs updates.
Add date support.
Add note in README about date support.
Update README, prepare() is no longer async
Handle column widths. WIP, needs work on API.
Update readme for previous.
Reworked file generation. Split packing from filesystem writing and sheet finalization.

Switched to litcoffee, will update documentation soon.
Add benchmark suite.
Update readme.
Add benchmark results to readme.
Add mkdir before benchmark
Switch to node-archiver from JSZip. Node-archiver offers async zip via node's zlib.

Updated 'excel' module to latest as it appears to have some issues unzipping zips created with this module.
I have no problems with Archive Manager or cli 'unzip' though. See https://github.com/joyent/node/issues/6384
Adding rows now streams directly into zip generation.

Updated api - we now use writer.createReadStream() rather than writer.pack(). Zip generation options
are passed in the constructor.
Get benchmarks & tests running again.
Re-add numberRegex, but support Numbers as well.
Add coffee-script dep so this can be properly included in projects
Remove dimensions. Ensure column definition occurs before sheetData.

While openoffice and numbers behave nicely, Excel (2007) explodes
if <cols> or <dimension> comes before <sheetData>. Absurd but true.
Update column test, prevent empty column tag from being written.