deposit: conferences id value synchronization

* Syncronizes value of the hidden conference_id field with the id
  from conferences field.

* Adds SychronizedField class which can be reused to do this.

Signed-off-by: Kamil Wieslaw Neczaj <kamil.neczaj@cern.ch>
deposit: conferences autocomplete tuninng

* Autocomplete fetching starts after 3 characters.

* Passes all items from ajax request up to 100.

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>
deposit: scrollbar for typeahead dropdowns

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>
global: enable of jasmine in configuration

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>
base: jquery-plugin creator adapted to requirejs

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>