Complete List.js usage for record search

Just complete the usage of the List.js library to implement the record
search. For this I am clearing the list with every new input and add
the search results again.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>
Add Underscore.js to throttle search via input

With underscore.js I have added the functionality of throttling the
input event used to generate search queries. This way, not too many
events are generated.

Signed-off-by: Konrad Reiche <konrad.reiche@gmail.com>