CLC-4102 Extract HttpRequester module
CLC-4102 Clean up cache expire calls before making more changes
CLC-4102 Mediacasts::CourseMedia does not need to subclass anything
CLC-4102 Rosters::Common does not need to subclass anything
CLC-4102 User::SearchUsers does not need to subclass anything
CLC-4102 Implement Live Updates support as ordered mix-ins
Refactored from AbstractModel class inheritance
CLC-4102 Use one cache for MyAdvising feed
Combines Live Update capabilities with short-expiration-on-exceptions
CLC-4102 Use one cache for Cal1Card feed
Generalize support for Live Update with short-expiration-on-exceptions
CLC-4102 Adapt Canvas::Proxy & MyFinAid to new code; fix bad cache-key
CLC-4102 Let MyFinancials leverage new Live Updates code
CLC-4102 Move existing merged models to new Live Updates code
CLC-4102 Fix missed RSpec; respond to code review
CLC-4102 Make FeedExceptionsHandled a mixin for cached feeds
whether they're Live Updates enabled or not.
CLC-4102 Improve MyFinancials comment
Merge pull request #3076 from raydavis/cacherefactor

CLC-4102 Reduce (& do not encourage) redundant caching