Bi-directional support

(Experimental for now)

Squashed commit of the following:

commit 486a7aa628fdd0079345e8662e273b528fd6568c
Author: Jack Senechal <jack@jacksenechal.com>
Date:   Thu Oct 31 15:36:12 2013 -0700

    revert mods to test/fixtures/sample.xml

commit 3819482436cd3ccfd3a6d5410288164de578cc5e
Author: Jack Senechal <jack@jacksenechal.com>
Date:   Thu Oct 31 15:31:57 2013 -0700

    adding diff to devDependencies

commit 969a354cf15840f011bde83140b806bfa76103c9
Author: Jack Senechal <jack@jacksenechal.com>
Date:   Thu Oct 31 15:25:47 2013 -0700

    Updated README.md

commit 3f9f626e5b23a56418af9048c332ac9eebf0d0f8
Author: Jack Senechal <jack@jacksenechal.com>
Date:   Thu Oct 31 15:16:34 2013 -0700

    exposing renderOpts and fixing a few tests

commit f61b65281251ea62758586ac4149d849cc7fe0e4
Author: Jack Senechal <jack@jacksenechal.com>
Date:   Thu Oct 31 03:09:53 2013 -0700

    lots of unit tests for the builder

commit c499afd83eb28cbcd5e644dc517cc78fc78f5a85
Merge: 26626d0 a2a4938
Author: Jack Senechal <jack@jacksenechal.com>
Date:   Mon Oct 28 17:34:12 2013 -0700

    Merge remote-tracking branch 'upstream/master'
    'npm test' passing

    Conflicts:
    	README.md
    	lib/xml2js.js
    	package.json
    	src/xml2js.coffee

commit 26626d0e75b7218aa535b987321ace9e616b8ac9
Author: Jack Senechal <jack@jacksenechal.com>
Date:   Fri Oct 25 04:10:08 2013 -0700

    Cleaned up and fixed a few bugs

commit 690b1c88accbfb6d872bce4d0bc934b5dd578887
Author: setumiami <guido@bitstorm.it>
Date:   Thu Jan 10 01:39:55 2013 +0100

    README.md modified.

commit 9bc9e9fc5d1179f9ebb977500989e82d817f5e77
Author: setumiami <guido@bitstorm.it>
Date:   Thu Jan 10 01:37:10 2013 +0100

    Added bi-directional conversion (xml2js and viceversa)