Add a search to look through all libraries #141
Description
Right now, a user can search through the contents of a single library by using the "view library in search results page" button and searching from there. But there isn't an easy way to search through all libraries at once, nor to know in which library a given bibcode is saved in. This issue is to implement some way to search through the contents of all of a user's libraries at once, and return information on which library a given bibcode is contained in.