GET /search (find cards and decks by keyword and flags)

[Roger-Heathcote]

Handler file /search/collection.js
GET /search?term=STRING&cards=BOOL&decks=BOOL?public=BOOL (auth) (same_user OR public) -> [
{ type: "deck", name: "French Vocabulary" }
{ type: "card", name: "Who was the french ambassador to russia in 1884" }
]
Note: we need to only search decks the user owns, or public decks.