- further fixes and enhancements to storage related things
 * added "delete" context menu to projectbrowserview
 * hence some updates to the contextmenu (not quite there yet)
 * added single select system for stores in the view
 * cleaned up event binding a bit
 * added preliminary support for renaming projects
 * slowly moving away from the backbone's "sync" method for localstorage, as it is highly unpractical in our case, and requires a ton of hack (but could be me)
- decided to switch to mostly custom persistence so now both backbone and browser storage set
a dataStore on the project, which is then used for custom persistence
 * added more gracefull handling of model destruction (in case a dataStore is set for the model)
 * modified the browser storage according to the above
 * added a destroyFile method to stores
 * added "auto cleanup" to browser storage : old files not present in the project anymore are deleted from storage
 * this fixes #48 and closes #57