Implementing a demo project

@mgorbach 
Assigning this to you, we can discuss at the standup tomorrow.
Closes #1.

Demo project for RZVinyl outlining many of the core features.

#### Features Demonstrated
- Importing
- ActiveRecord extensions
   - Delete
   - Count
   - Fetch by attributes
   - Fetch by primary key
- "Scratch" context for editing

#### Features Not Demonstrated
- Creating a new object in-app
   - Requires lots of UI
- Direct query using AR extensions (not using fetched results controller)
   - No good use for it here, will document in README
Whoops. It isn't. Good catch!

> On Jun 24, 2014, at 6:49 PM, Michael Gorbach <notifications@github.com> wrote:
> 
> In Example/RZVinylDemo/View Controllers/RZPersonDetailViewController.m:
> 
> > +
> > +- (void)setEditing:(BOOL)editing animated:(BOOL)animated
> > +{
> > +    [super setEditing:editing animated:animated];
> > +    
> > +    self.personView.nameTextField.enabled = editing;
> > +    self.personView.bioTextView.editable = editing;
> > +    self.personView.deletePersonButton.enabled = !editing;
> > +    
> > +    if ( editing ) {
> > +        
> > +        // Create a "scratch" context for editing
> > +        self.scratchContext = [[RZCoreDataStack defaultStack] temporaryManagedObjectContext];
> > +        
> > +        // Get a copy of this person from the scratch context
> > +        self.editingPerson = [RZPerson rzv_objectWithPrimaryKeyValue:self.person.remoteId createNew:NO];
> @ndonald2 I'm confused here. How does this get an object in the editing context, when you are not specifying the MOC?
> 
> —
> Reply to this email directly or view it on GitHub.