Added caching to the predict views.

This change adds caching to the predict views using django's built-in caching.

Current timeouts:

    | Type           | Time (minutes) |
    |----------------+----------------|
    | Match          |              1 |
    | 4-Player Swiss |              5 |
    | SE Bracket     |             10 |
    | Round Robin    |              5 |
    | Proleague      |              5 |



This should probably be added to the settings file like so:

    CACHE_TIMEOUTS = {
        'match': 60,
        ...
        'proleague': 5 * 60
    }

Needs to have a cache backend set up in the settings. You can use a dummy
one before setting up a real one.

See: https://docs.djangoproject.com/en/1.5/topics/cache

Dummy cache:

    CACHES = {
        'default': {
            'BACKEND': 'django.core.caches.backends.dummy.DummyCache'
        }
    }