Removed unrelated git submodule

Looked like a Sencha Touch 2 git submodule was committed as part of lavaca
work, so is believed to be an accidental / unrelated modification.
Fixed issue preventing lavaca from building

Lavaca has a dependancy on jquery, however it expects that there is an
index.js file.  This is no longer present.

According to Lavaca v2.3.3 the dependency is changed to expect a jquery.js
file, which turns out to be present.

I preferred to apply this fix rather than performing the update to v2.3.3.
Cleaned up cordova build files for lavaca
Updated lavaca assets

Including icons, screenshots and Cordova config files