Replicate namedtuple functionality

The ImmutableFactory is just a thin wrapper that allows you to do this in one step:

from immutable import ImmutableFactory

attributes = (('using', 'first'), ('these', 'second'), ('attrs', 'third'))

# don't worry about the extra kwargs for now :)
ATuple = ImmutableFactory.create(attributes, keys=False, values=False, items=False)
ATuple  # Immutable(using='first', these='second', attrs='third')

# dot-access attributes
ATuple.using  # 'first'
Atuple.these  # 'second'
ATuple.attrs  # 'third'

# index-access attributes
ATuple[0]  # 'first'
ATuple[1]  # 'second'
ATuple[2]  # 'third'
ATuple[-1]  # 'third'

# the class name is *always* `Immutable` now
ATuple.__class__.__name__  # 'Immutable'

Some extra bells and whistles (don’t get too excited)

Most of the time, we don’t care about the order. This allows us to instantiate in a much cleaner style:

from immutable import ImmutableFactory

ATuple = ImmutableFactory.create(using='first', these='second', attrs='third',
                                 keys=False, values=False, items=False)

# note that there's no predictable order here
ATuple  # Immutable(these='second', using='first', attrs='third')

# dot-access attributes
ATuple.using  # 'first'
Atuple.these  # 'second'
ATuple.attrs  # 'third'

# doesn't really make sense to index-access attributes now, so don't.

# the class name is *always* `Immutable` now
ATuple.__class__.__name__  # 'Immutable'

Additionally, it’s helpful to have dict-like keys, values, and items. These