Added site-wide caching.

The cache function uses the view name and looks up the number of
seconds to store the cache in settings.CACHE_TIMES. Default is
60 seconds.

Example:

_MINUTE = 60
_HOUR = 60 * _MINUTE
_DAY = 24 * _HOUR

CACHE_TIMES = {
    "aligulac.views.home": _HOUR,
    "ratings.predictviews.pred_sebracket": _HOUR,

    "aligulac.views.staff": None
}

The above example caches "home" and "pred_sebracket" for an hour,
disables caching for "staff" and caches all other pages for a
minute (default).
Merge pull request #80 from Prillan/cache

Added site-wide caching.