Refactor SQL Query for getting public tags and replace will_paginate with kaminari

 * Using EXPLAIN, refactor ActsAsTaggableOn::Tag.public_tags to reduce cost from "18.18..18.35" to "14.99..15.15"
 * Replace will_paginate with kaminari since kaminari:
   * does not clobber the ActsAsTaggableOn::Tag.public_tags query
   * does not pollute any objects like ActiveRecord::Base
   * has a cleaner UI
 * Remove WillPaginate initializer
 * Generate kaminari config
 * Generate bootstrap kaminari theme
 * Refactor decorators to delegate pagination methods to kaminari
 * Refactor MyGists::Search to delegate kaminari pagination methods to scope
 * Refactor MyGists::Public.tags to use kaminari
 * In the views, replace will_paginate helper with kaminari helper
Merge pull request #38 from simeonwillbanks/refactor

Refactor ActsAsTaggableOn::Tag.public_tags and Use Kaminari