Made changes to database and search routes

Made the following changes:
1) Separated Slick Database access from main database access
2) Separated Slick driver name into single import
3) Added two more fields to BookQuery
4) Created Binder for BookQuery

TODO
1) Separate the Slick driver configuration to the application.conf file as db.default.slickdriver
2) Compact the database access such that all statements are executed in a single session