Add ability to save/load queries from the UI as default slush feature

[sashamitrovich]

[grtjn]

There is some extra code involved, like a helper object to show modals (I have a service that makes using modals for most common cases very easy). It might also take some effort to setup back-end security properly to put the queries in a separate collection/folder, exclude them from normal search, and have another modal that shows a simple search on just the saved queries..

One could also consider extending the idea to do some organization of saved queries. Mark them as shared or not, hide them from other or not, extra properties, tracking of query usage, etc..