Changed behaviour of boolean dtx attributes.

These were previously undocumented and unspecified, and i changed my
mind on their behaviour.

Now usage is like this:

    <div dtx-show="true">Always show</div>
    <div dtx-show="false">Never show</div>
    <div dtx-show="someBoolean">Show if `someBoolean` is true</div>
    <div dtx-hide="someBoolean">Hide if `someBoolean` is true</div>
    <div dtx-show="someString!=null">$someString</div> // Only show if someString is not null
    <div dtx-show="someArray.length>0">...</div> // Only show if someArray is not empty

The difference though is that now you must explicitly declare your boolean attributes.  This will
break some of my code, but as it was undocumented, untested and unspecified, I'm happy to change it.

Doing this also resulted in me fixing issues with inline variable initialization, (public var x=0;)
which is working correctly and unit tested now.
Keep interpolation tests together
Added @:dtxdebug metadata to print the fields that are created.

Added the supporting files as needed.
Major refactor of the way named elements and partials work

Before, every time you an element needs to be known at runtime, it would
add a data-dtx-id attribute, and then do a find() at runtime.

Apart from being slow, this created issues when multiple widgets with the same
named partials occupied the same DOM space - it would match the element in both
widgets, not just one.

The solution is to map all of the referenced elements in the widget constructor,
save them in an array reference, and then simply refer to the array reference.

This is faster and more reliable.

I've added new unit tests to verify the behaviour, and they're all passing on neko.
Remove data-dtx-id from src during constructor

So that the html is not polluted while you're using it
Version bump
Swapped package.sh for bundle.sh