Fix for pom generation
Some initial meanderings.
Dropped idea of AssetType as asset type identifier.
AssetType is now the key class for managing all assets of a type.
Added support for loading assets from data (programatic creation)
Added support for disposing assets.
Addressing #2 - adding support for resolving asset by urn in modules.

Introduces support for formats (loading files into asset data) and setting the module environment. When the environment is set, or when a new format is registered, all unloaded assets are discovered and recorded in a table for loading. The table is not strictly necessary yet, but will allow for both overrides and incomplete urn resolution down the track.
Merge pull request #10 from immortius/develop

Support for loading assets out of modules via ResourceUrn