RFR - Ma search buses

Both tests passing!
issue #43 
This condition will probably not run when you want it to.  If I enter a search param that doesn't match any buses, for example "aslkdjfalksd", the `if params[:search]` condition will still be met so we'll never hit the `elsif`.  

You could instead nest your conditional:

```ruby
  def index
    if params[:search]
      @buses = Bus.search(params[:search]).order(:number)
      
      if @buses.empty?
        @buses = Bus.order(:number)
        flash[:notice] = "Could not find your search term"
      end
    else
      @buses = Bus.order(:number)
    end
  end
```