Support multiple design documents

The last argument is assumed to be the CouchDB url, as normal, but all
arguments between <command> and <url> are assumed to be couch app paths.
Merge branch 'master' of https://github.com/rmg/node.couchapp.js
Add directory config
Add directory config
Add directory config
Add directory config
Add directory config
Correct the coding style from 4 space tabs to 2 space tabs
Merge pull request #66 from philwestwell/master

Directory-based config with multiple app files, pre-processing and post-processing
Update package.json
Compile .coffee files on push if coffee-script is installed
Separate dev server in its own function
Merge upstream
Fix dc option checking.

 isUsingDirectoryConfig() is invoked once before argument processing, and once after.
 If '-dc' is not specified, second time the check fails because the argv is empty.
 This commit makes it use cached valued for all but first invokation.