== Usage
cache = require('dobi-cache')(config)
app.get '/', (req, res, next) ->
console.log 'do something'
cache('5 minutes', (next) ->
next 'hello world'
)(req, res, next)
app.get '/foo', cache '5 minutes', (next) ->
next 'data'
app.get '/bar', cache {
age: 300
query: ['name', 'title']
}
app.get '/bar', cache {
age: '5 minutes'
query: '*'
}