Complete Rewrite

I started off trying to fix https://github.com/ArcBees/gwtp-eclipse-plugin/issues/85 but things got a bit away from me.

Update Site: http://3-dot-pushstateslash.appspot.com/repository  (Probably only works on Luna) **Reset your perspective after install**

I battled to get started and I thought at first that the project was a bit of a mess, but I think the mess is with SWT itself so the new version is just as messy and I've only really moved things around.

By the time I realized that I'd already gone too far with the rewrite and this has big advantages over the old plugin so I continued.

# Info For Contributors

This should be simpler to build, just checkout the project and run `mvn install` and you should produce a working update site in gwtp.plugin.site/target.  I want to get to a much faster update cycle for the plugin so hopefully we can get the entire deploy down to a single command

You should also be able to do a maven import into eclipse of the 5 projects.  I think you might need a couple of plugins to be installed and maybe some maven connectors.  When I have a chance I'll start from a clean eclipse install and document what is needed.

# Info For Users
This is not the same plugin as before and some features are missing.  Others might be buggier than you expect.

The entire plugin now works offline, which makes it much much faster.  I'm on a slow connection and presenter creation has gone from taking more than a minute to instantaneous. 

Project Creation and Presenter Creation have become new Wizards and moved to the new menu ->

![new wizards](http://i.imgur.com/vmaDvH4.png)

## Project Creation
Project Creation is much more on rails.  At any point during the process you should be able to click finish and get a working project, which should make it much easier for new users to experiment with GWTP.

Instead of using archetypes you now create a standard GWTP project and then add features to it.  So far there are just 4 features but more should come soon:

![feature selection](http://i.imgur.com/0wJpa8I.png)

* The Universal Analytics and GWT-Pushstate snapshots are not in sonatype so you'll have to install them manually.  You should use [my branch of GWT-Pushstate](https://github.com/rdwallis/gwt-pushstate/tree/ohfix) it has some bug fixes from master

Depending on what features you choose you'll get options to customize them:
![feature configuration](http://i.imgur.com/v2AyEO2.png)

Click Finish and you're done

## Presenter Creation
This is very similar to how it was: The Popup Tab is gone and you can just choose isPopup instead to create a nested or widget popup depending on what's selected.

I've removed the option to make a nametoken crawlable.  With gwt-pushstate you don't need this anymore because you can get the token on the server.

This needs some cleanup and help menus still.  I think the tabs can be removed since there's only one option for presenter widgets.

# Other Things

The plugin now includes the ide-templates, and I've simplified the templates as well.  Mainly this is because I have a very slow internet connection and fetching templates used to be very slow for me.

I couldn't get velocity to work because of https://bugs.eclipse.org/bugs/show_bug.cgi?id=396554 so I'm using a custom parser that will break if you do anything fancy.

You also have to zip the templates up before compile because I couldn't work out how to keep the folder heirachy otherwise.
Up to discussion, but HasXXXHandlers is also useful in some, but not all, situations