Remove features that are not commonly used

[markohlebar]

It seems that the usage really boils down to BINDViewModel and BIND.
In terms of simplifying the interface we should trim unnecessary features like
shorthands BINDSL, BINDSR, BINDOS and BINDS which clutter the DSL and
autocompletion.

[benvium]

I find myself using BINDO quite a lot, especially for marking computed properties as requiring updating.

For example:

[BINDO(self, quantity) observe:^(id observable, NSNumber *value, NSDictionary *observationInfo) {
            [self willChangeValueForKey:@"canDecrement"];
            [self didChangeValueForKey:@"canDecrement"];
        }];
...
- (BOOL)canDecrement {
    return self.selectedItem.quantity > MIN_AMOUNT;
}

.. though I'm sure the above could be achieved in a different way.

[markohlebar]

@benvium good shout! BINDO is pretty useful I agree. I think shorthands are a waste of space though :)
I don't want to be precious about features and maintain stuff that nobody uses.